| Title | Pages | Publication | Code | Date | Publisher | System (Setting) |
|---|
 I Am It And It Is I | Event (U) |  Eldritch Edition | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
 I Am Not Dead Yet! | 2001 |  talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
 I Am Providence | | I Am Providence | | 2014 | Self Published | I Am Providence
| |
| I Am the Fourth Wall | | I Am the Fourth Wall | | 2019 | Slinky Gibbon Games | I Am the Fourth Wall
| |
 I am Under the Command of Others | | House of Tindalos | | n/a | Self Published | Mythos
| |
| I Got the Part! | Event (F) | Rosemary's Baby | | n/a | Self Published | Mythos
| |
| I Hate My Job * | 2013 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| I Look Like What? | |  Chaosium Digest | v23n06 | Mar 1998 | Chaosium | Mythos
| |
| I See a Bird. No Wait … a Byakhee | 2001 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| I Want a New Drug | 57 |  Interface | 6 | 1992 | Prometheus Publishing | Call of Cthulhu (Cyberpunk)
| |
| I Want to Break Free | 2020 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| I Want to Play | |  I Want to Play | FXC-07 | 2019 | Stygian Fox | Call of Cthulhu (Now)
| |
| I Want You to Kill the Ice Cream Man | 233-240 | 40 Adventures for Call of Cthulhu | | 2002 | Self Published | Call of Cthulhu (Now)
| |
| I Want You to Kill the Ice Cream Man | | Chaosium Digest | v26n04 | Jul 1998 | Chaosium | Call of Cthulhu (Now)
| |
| I Want You to Kill the Ice Cream Man | 1-8 | I Want You to Kill the Ice Cream Man | | 2000 | Self Published | Call of Cthulhu (Now)
| |
| I Want You to Kill the Ice Cream Man | 7-15 | Opifex Bimonthly | 17 | Jan 1999 | Self Published | Call of Cthulhu (Now)
| |
| I Was a PC Detective, or Can You Find Cthulhu in Three Easy Lessons (If That's Your Idea of a Good Time) | 1, 22-23 |  Game's Afoot | 9 | 1992 | Zirlinson Publications | Call of Cthulhu (Classic)
| |
| I was a Teenage Cthulhu Chaser! | 72-95 | The Unspeakable Oath | 8/9 | Jun 1993 | Pagan Publishing | Call of Cthulhu (Atomic)
| |
| Ia! Ia! | Event (F) | The Thousand Young | CT65 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Ia! Ia! Shudde M'ell! | Event (F) | Aspirations of Ascension | CT43 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Iaa! Cthulhu! Fhtagn! | | Iaa! Cthulhu! Fhtagn! | | 2016 | Sphinx Speileverlag | Iaa! Cthulhu! Fhtagn!
| |
| Ian Hardaway | Character (F) | The Sleeper Below | CT63 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Iatrophobia | Event (R) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Ibbix the Harbormaster | Ally (R) | Dreamlands | CAO1307-1 | 1997 | Chaosium | Mythos
| |
| Ibrahim Amin | Ally (C) | Legends of the Necronomicon | CAO1303-1 | 1996 | Chaosium | Mythos
| |
| The Icarus Project | 88-119 | Worlds of Cthulhu | 2 | Feb 2005 | Pegasus Press | Call of Cthulhu (Strange Aeons: Far Future)
| |
| Ice Cream Man | | Ice Cream Man | | May 2019 | Chaosium | Call of Cthulhu (Now)
| |
| The Ice of Paulet 7 | Aug 2018 | Reckoning of the Dead | | n/a | Self Published | Call of Cthulhu (Strange Aeons: Far Future)
| |
| Ice Shaft | Support (F) | Never Night | CT50 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Ice Storm | Event (F) | For the Greater Good | CT64 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Iceland | 126-151 |  The Two-Headed Serpent | CHA23125 | 2017 | Chaosium | Call of Cthulhu (Classic)
| |
| Icon of the Nameless Pharaoh, Lost from History | Support (R) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| The Iconodule | Oct 2020 | shoggoth.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| The Icosahedron - A History | 76-77 | Lurking Fears | 0001 | Jan 1990 | Triad Entertainments | Call of Cthulhu (Classic)
| |
 The IDEAL Conceal | | The Dark Times | 1 | Aut 2017 | Self Published | Call of Cthulhu (Now)
, Dark Conspiracy
| |
| Ideas for Cybercthulhu | | Chaosium Digest | v02n11 | Jun 1993 | Chaosium | Call of Cthulhu (Cyberpunk)
| |
| Idiosynxratic Magic Expanded | 28-32 | Rough Magicks | PELGT09 | 2009 | Pelgrane Press | Trail of Cthulhu
| |
| Idol from R'lyeh | Support (C) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Idol of Bokrug | Artifact (C) | Dreamlands | CAO1307-1 | 1997 | Chaosium | Mythos
| |
| Idol of the Abomination | Support (F) | The Path to Y'ha-nthlei | CT24 | 2009 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| The Idol of Thoth | | The Idol of Thoth | | Dec 2017 | Stygian Fox | Call of Cthulhu (Classic)
| |
| If I Ran the Zoog | Adventure (U) | Dreamlands | CAO1307-1 | 1997 | Chaosium | Mythos
| |
 If I Ran the Zoog Deck | | Robo's Mythos CCG Web Page | | n/a | Self Published | Mythos
| |
| If Only In My Dreams | 2017 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| Igor Ichor Promo Card | | Igor Ichor Promo Card | | Mar 2009 | Steve Jackson Games | Munchkin
| |
| Ikiaq * | | Arkham Nights 2018 Cards | | 2018 | Fantasy Flight Games | Arkham Horror: The Card Game
| |
| Il Mondo Occulto | Location (R) | Expeditions of Miskatonic University | CAO1301-1 | 1996 | Chaosium | Mythos
| |
| Ilarnek | Location (C) | Dreamlands | CAO1307-1 | 1997 | Chaosium | Mythos
| |
| Ilek-Vad | 196-227 | The Sense of the Sleight of Hand Man | APU8001 | 2013 | Arc Dream Publishing | Call of Cthulhu (Dreamlands)
| |
| Ill Omen | Event (R) | New Aeon | CAO1311-1 | 1997 | Chaosium | Mythos
| |
 Ill Omens Art Pack | | Ill Omens Art Pack | | Dec 2017 | Chaosium | Call of Cthulhu (Classic)
| |
| The Ill-Made Knight * | | The Once and Future King | | 1999 | Self Published | Call of Cthulhu (Classic)
| |
| The Illuminated Order | 41-46 | Abyss Quarterly | 51 | 1993 | Ragnarok Games | Call of Cthulhu (Classic)
| |
| Illuminating Manuscripts: The G’harne Fragments | 19-22 | Polaris | 1 | Sum 1987 | Self Published | Call of Cthulhu (Classic)
| |
| The Ilsley Variant | 37-48 | Dead Leaves Fall | CHA0406 | 2011 | Chaosium | Call of Cthulhu (Classic)
| |
| I'm Surrounded by Witches | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Images of Doom | | Tales of Terror (II) | PAG2102 | 1996 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Immurement | Event (F) | Denizens of the Underworld | CT62 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Imperfects | Oct 2005 | shoggoth.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Implant Fear | Event (U) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Implant Fear | Event (F) | Secrets of Arkham | CT32 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Important Members | 27-34 | The Golden Dawn | PAG1004 | 1996 | Pagan Publishing | Call of Cthulhu (Gaslight)
| |
| An Impossible Murder | | More Tales of Terror | PAG2105 | 2000 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Imprisoned With the Pharaohs | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Impulsive | 54 | Dark Passions | WDF23200 | 2008 | WildFire Games | Framewerk (CthulhuTech)
| |
| In a City of Bells and Towers | | Dagon | 22,23 | Sep 1988 | Self Published | Call of Cthulhu (Classic)
| |
| In a City of Bells and Towers | C:117-130 |  Horror on the Orient Express | CHA23130 | 2014 | Chaosium | Call of Cthulhu (Classic)
| |
| In a City of Bells and Towers | C:121-129 | Horror on the Orient Express | CHA2331-X | 1991 | Chaosium | Call of Cthulhu (Classic)
| |
| In a Different Light * | 1-34 | In a Different Light | | 2011 | Cthulhu Reborn | Call of Cthulhu (Classic)
| |
| In A Different Light, Part 1 | | Chaosium Digest | v29n12 | Jan 2000 | Chaosium | Call of Cthulhu (Classic)
| |
| In A Different Light, Part 2 | | Chaosium Digest | v30n01 | Jan 2000 | Chaosium | Call of Cthulhu (Classic)
| |
| In A Different Light, Part 3 | | Chaosium Digest | v30n02 | Jan 2000 | Chaosium | Call of Cthulhu (Classic)
| |
| In A Different Light, Part 4 | | Chaosium Digest | v30n03 | Jan 2000 | Chaosium | Call of Cthulhu (Classic)
| |
| In A Different Light, Part 5 | | Chaosium Digest | v30n04 | Jan 2000 | Chaosium | Call of Cthulhu (Classic)
| |
| In an Unmarked Grave | Event (F) | Sleep of the Dead | CT30 | 2009 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| In and Out of the Academic World | 64-67 | Miskatonic University | CHA2352 | 1995 | Chaosium | Call of Cthulhu (Classic)
| |
| In Captivity | 34-38 | Guide to the Pacific Front | MPS01051CS | 2014 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| In Darkness, Power | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| In From the Cold | | In From the Cold | | 2017 | Golden Goblin Press | Call of Cthulhu (Classic)
| |
| In Media Res | 146-161 | Out of the Vault | PAG1009 | 2002 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| In Media Res | 56-63 | The Unspeakable Oath | 10 | Jan 1994 | Pagan Publishing | Call of Cthulhu (Now)
| |
| In Media Res Live Action Roleplaying Report | 25 | The Unspeakable Oath | 11 | Jan 1995 | Pagan Publishing | Call of Cthulhu (Now)
| |
| In Nomine Diabolis | | More Tales of Terror | PAG2105 | 2000 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| In Rags | Support (C) | Eldritch Edition | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| In Requiem | 174-175 | Cthulhu Apocalypse | PELGT40 | 2015 | Pelgrane Press | Trail of Cthulhu
| |
| In Requiem | 63-64 | Slaves of the Mother | PELGT31 | 2014 | Pelgrane Press | Trail of Cthulhu
| |
| In Rerum Supernatura | 189-192 | Call of Cthulhu | CHA2336 | 1992 | Chaosium | Call of Cthulhu (Classic)
| |
| In Rerum Supernatura | 108-113 | Call of Cthulhu | CHA2386 | 1999 | Chaosium | Call of Cthulhu (Classic)
| |
| In Search of Sanity | 4-55 | In Search of Sanity | PZO90109 | 2016 | Paizo Publishing | Pathfinder
| |
| In The Beginning | 16-25 | Beyond the Mountains of Madness | CHA2380 | 1999 | Chaosium | Call of Cthulhu (Classic)
| |
| In The Cards | Oct 2009 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| In the Clutches of Chaos | | In the Clutches of Chaos | AHC34 | 2019 | Fantasy Flight Games | Arkham Horror: The Card Game
| |
| In the Clutches of Mami Wata | 59-72 | Secrets of the Congo | CHA0387 | 2010 | Chaosium | Call of Cthulhu (Classic)
| |
| In the Court of the Dragon | Conspiracy (F) | Touched by the Abyss | CT58 | 2012 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| In the Forests, the Shadows | | Chaosium Digest | v24n03 | Mar 1998 | Chaosium | Call of Cthulhu (Classic)
| |
| In the Forests, The Shadows | | More Tales of Terror | PAG2105 | 2000 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| In the Grip of Madness | 27-34 | Worlds of Cthulhu | 2 | Feb 2005 | Pegasus Press | Call of Cthulhu (Classic)
| |
| In the Gutter | Event (U) | Forgotten Cities | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| In the Matter of Mr Barnabas Marsh | | House of Tindalos | | n/a | Self Published | Mythos
| |
 In The Mountain | 01:00 |  Eternal Lies Suite | PELGT17 | 2010 | Pelgrane Press | Trail of Cthulhu
| |
| In The Nick of Time | Event (U) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| In the Service of One's Country | 34-47 | Investigator's Guide to the Secret War | MPS01031CS | 2013 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| In the Shadow of the Valley * | 2019 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| In the Shadows of Death | 24-39 | In the Shadows | CHA2357 | 1995 | Chaosium | Call of Cthulhu (Classic)
| |
| In the Vault | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| In the Wake of Gods | 2018 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| In the Wake of the Sleeper | Event (F) | The Order of the Silver Twilight | CT33 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| In the Watches of the Night | 2005 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| In the Waters of Wyman | 8-23 | White Wolf | 4 | Oct 1986 | White Wolf Games | Call of Cthulhu (Classic)
| |
| In the Woods, No One Can Hear You Screaming | 54-55 | Dark Passions | WDF23200 | 2008 | WildFire Games | Framewerk (CthulhuTech)
| |
| In Too Deep | | In Too Deep | AHC53 | 2020 | Fantasy Flight Games | Arkham Horror: The Card Game
| |
| In Whom We Trust | 1996 | Four Letters At Random | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| In Whom We Trust * | 1-33 | In Whom We Trust | | 2016 | Self Published | Call of Cthulhu (Classic)
| |
| Inca Unconquered | 1998 | Ubar | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| An Incident at the Border | 86-103 |  Mythos Expeditions | PELGT37 | 2014 | Pelgrane Press | Trail of Cthulhu
| |
| Incident in Iraq | 171-180 | Walker in the Wastes | PAG1002 | 1994 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Incomprehensible Machine | Support (R) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Inconspicuous Zoog | Character (F) | Sleep of the Dead | CT30 | 2009 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| An Inconvenience to Travellers | 1997 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Incredible Incunabula: Fifty Works of Arcane and Forgotten Lore for Call of Cthulhu | 44-47 | Space Gamer | 86 | Jul 1989 | Steve Jackson Games | Call of Cthulhu (Classic)
| |
| Incriminating Evidence | Event (F) | Scooby Doo Set 3 | | n/a | Self Published | Mythos
| |
| The Incriminating Letter | 1-10 | The Incriminating Letter | | 2003 | Self Published | Call of Cthulhu (Now)
| |
| Indebted | Support (F) | Denizens of the Underworld | CT62 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Independence Square | Support (C) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Independent Operator | Character (U) | Masks of Nyarlathotep | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Indian Picture Rock | Location (F) | Scooby Doo Set 2 | | Mar 1999 | Self Published | Mythos
| |
| Indiana Jones for CoC | | Chaosium Digest | v23n02 | Feb 1998 | Chaosium | Call of Cthulhu (Classic)
| |
| Indigo: After the End of the World | | Indigo: After the End of the World | | Feb 2018 | Chaosium | Call of Cthulhu (Now)
| |
| Induce Terror | Event (F) | The Mark of Madness | CT66 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Inducement | Support (U) | Forgotten Cities | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
 Industrial Espionage | 94-95 | Unveiled Threats | WDF23600 | 2011 | WildFire Games | Framewerk (CthulhuTech)
| |
| The Inevitable | 2016 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| Infected by Madness | Event (C) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Infected by Madness | Event (F) | Secrets of Arkham | CT32 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Infernal Obsession | Support (F) | The Antediluvian Dreams | CT21 | 2009 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Inferno | 1-32 | Whispers in the Dark | 0003 | Oct 1993 | Triad Entertainments | Call of Cthulhu (Now)
| |
| Infest | | Infest | | n/a | Self Published | Call of Cthulhu (Now)
| |
| Infestation | 1997 | Ubar | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Infested Cemetery | Support (U) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Infinite Gulfs of Darkness | | Infinite Gulfs of Darkness | | 2021 | Ludonova | Arkham Noir
| |
| Infirmary | Support (F) | Words of Power | CT54 | 2012 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Influenza | Event (C) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Informant | Character (C) | Eldritch Edition | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Inhabitants of the Realms | 216-262 | Secrets of Japan | CHA2392 | 2005 | Chaosium | Call of Cthulhu (Classic)
| |
| The Inheritance | 33-43 | Horror Stories From the Red Room | CHA0413 | 2013 | Chaosium | Call of Cthulhu (Classic)
| |
| Inheritance | | Inheritance | | 2019 | Chaosium | Call of Cthulhu (Classic)
| |
| The Inheritor | 5-28 | The Thing at the Threshold | CHA2339 | 1992 | Chaosium | Call of Cthulhu (Classic)
| |
| Initialization | 2018 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| Initiate of Dagon | Character (F) | The Sleeper Below | CT63 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Initiate of Huang Hun | Character (F) | Curse of the Jade Emperor | CT48 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Initiation | Event (F) | The Order of the Silver Twilight | CT33 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Initiation of Glaaki | Event (F) | Aspirations of Ascension | CT43 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Ink and Blood | Feb 2017 | shoggoth.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Ink Man | Oct 2019 | shoggoth.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Inland Waterways | 37 | Green and Pleasant Land | CHA2320 | 1987 | Chaosium | Call of Cthulhu (Classic)
| |
| Inmasking the Villian | Event (F) | Scooby Doo Set 1 | | n/a | Self Published | Mythos
| |
| An Inner Call | | An Inner Call | | Sep 2020 | Chaosium | Call of Cthulhu (Classic)
| |
| The Inner Order Curiculum | 43-49 | The Golden Dawn | PAG1004 | 1996 | Pagan Publishing | Call of Cthulhu (Gaslight)
| |
| Inner Sanctum | Support (U) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| The Innocent | 55-84 | Caligo Accendendum Tournament | CHA0309 | 2004 | Chaosium | Call of Cthulhu (Dark Ages)
| |
| The Innocents | Oct 2005 | shoggoth.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Innsmouth 2000 | 101-105 | Ye Booke of Tentacles | 3 | 2000 | The Chaos Society | Call of Cthulhu (Now)
| |
| The Innsmouth Connection | 31-43 | Before the Fall | CHA2377 | 1998 | Chaosium | Call of Cthulhu (Classic)
| |
| The Innsmouth Conspiracy | | The Innsmouth Conspiracy | AHC52 | 2020 | Fantasy Flight Games | Arkham Horror: The Card Game
| |
| Innsmouth Courier | Location (C) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| The Innsmouth Cover-up | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Innsmouth Curios | 46-52 | The Arkham Gazette | 2 | Nov 2013 | Sentinel Hill Press | Call of Cthulhu (Classic)
| |
| The Innsmouth Deck | | Chaosium Digest | v21n06 | Sep 1997 | Chaosium | Mythos
| |
| The Innsmouth Deck | | Robo's Mythos CCG Web Page | | n/a | Self Published | Mythos
| |
| Innsmouth Deck | | Thastygliax's Vault | | n/a | Self Published | Mythos
| |
| Innsmouth Escape | | Innsmouth Escape | TLC3401 | 2008 | Twilight Creations | Innsmouth Escape
| |
| Innsmouth Express | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Innsmouth Gold | 53-61 | The Arkham Gazette | 2 | Nov 2013 | Sentinel Hill Press | Call of Cthulhu (Classic)
| |
| Innsmouth Horror Expansion | | Innsmouth Horror Expansion | VA57 | 2009 | Fantasy Flight Games | Arkham Horror
| |
| Innsmouth Independence Day | 133-178 | The Eldritch New England Holiday Collection | GGP2005 | 2020 | Golden Goblin Press | Call of Cthulhu (Classic)
| |
| The Innsmouth Lighthouse | 1 | The Innsmouth Lighthouse | | 2009 | Self Published | Risus
| |
| The Innsmouth Look | Support (C) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Innsmouth Look | Adventure (F) | Eric Johnson Mythos Collection | | n/a | Self Published | Mythos
| |
| The Innsmouth Look | Event (R) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Innsmouth Shoggoth | Character (R) | Eldritch Edition | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| The Innsmouth Threat | Story (F) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| The Innsmouth Threat | Story (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| The Innsmouth Threat | Story (F) | Secrets of Arkham | CT32 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Innsmouth Troublemaker | Character (F) | Call of Cthulhu The Card Game | CT18 | 2008 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Innsmouth Troublemaker | Character (C) | Forbidden Relics | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Innsmouth Weapons Deck | | Chaosium Digest | v20n11 | Aug 1997 | Chaosium | Mythos
| |
| Innsmouth Weapons Deck | | Robo's Mythos CCG Web Page | | n/a | Self Published | Mythos
| |
| Innsmouth's Burying Grounds | 9-15 | The Arkham Gazette | 2 | Nov 2013 | Sentinel Hill Press | Call of Cthulhu (Classic)
| |
| Inquanok | 105-142 | The Sense of the Sleight of Hand Man | APU8001 | 2013 | Arc Dream Publishing | Call of Cthulhu (Dreamlands)
| |
| Inquisitive Chinese Intellectual/Morose Veteran Of The Great War | Investigator (F) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Insane in the Membrane! | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Insane Insight | Spell (F) | Sesqua Valley | | n/a | Self Published | Mythos
| |
| Insanitarium | | Insanitarium | | 2019 | Chaosium | Call of Cthulhu (Classic)
| |
| Insanity and Faith in Averoigne | 85-88 | Worlds of Cthulhu | 4 | Jan 2006 | Pegasus Press | Call of Cthulhu (Dark Ages)
| |
| Insanity, Society and the Law | 43-50 | Taint of Madness | CHA2354 | 1995 | Chaosium | Call of Cthulhu (Classic)
| |
| Insect From Shaggai | Monster (F) | Unlimited | CAO1306-1 | 1997 | Chaosium | Mythos
| |
| Insect From Shaggai | Monster (F) | Unlimited | CAO1306-1 | 1997 | Chaosium | Mythos
| |
| Insect Swarm | Character (F) | The Thing from the Shore | CT23 | 2009 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Inside Information | Event (C) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Inside Information | Event (F) | Call of Cthulhu The Card Game | CT18 | 2008 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Inside Man | Character (F) | The Unspeakable Pages | CT57 | 2012 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Inside Out | 49 | The Whisperer | 5 | Aut 2003 | Severn Valley Press | Call of Cthulhu (Now)
| |
| Inside the Reich | 15-21 | Keeper's Guide to the Secret War | MPS01032CS | 2013 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Inside-Out Hours | Event (U) | Forgotten Cities | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Insidious Ululation of the Invisible Supplicants | Spell (U) | New Aeon | CAO1311-1 | 1997 | Chaosium | Mythos
| |
| Inspector John LeGrasse | Character (F) | The Sleeper Below | CT63 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Inspector John Legrasse, Cop in the Know | Character (U) | Unspeakable Tales | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Inspector Li Flint | Character (F) | Curse of the Jade Emperor | CT48 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Instability in the Mythos | | Chaosium Digest | v27n05 | Jan 1999 | Chaosium | Mythos
| |
| Instability in the Mythos | Event (C) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Instability in the Mythos | Event (C) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Insta-Plots | 133-134 | Cthulhu Casebook | CHA3305 | 1990 | Chaosium | Call of Cthulhu (Classic)
| |
| The Institute for Paranormal Studies: A Cult Profile | 31-40 | Interface | 6 | 1992 | Prometheus Publishing | Call of Cthulhu (Cyberpunk)
| |
| Institutions, Organizations and Power Groups in Japan | 166-178 | Secrets of Japan | CHA2392 | 2005 | Chaosium | Call of Cthulhu (Classic)
| |
| Instruments of Glass and Metal | Support (U) | Eldritch Edition | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Insubstantial Insect | Character (U) | Masks of Nyarlathotep | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Integratron | 2010 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| Intelligence Agent | Character (F) | For the Greater Good | CT64 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Intelligence Report #5743 | 1997 | delta-green.com | | n/a | Pagan Publishing | Call of Cthulhu (Delta Green)
| |
| Inter Solar System Species Index | | Chaosium Digest | v07n07 | Sep 1994 | Chaosium | Call of Cthulhu (Classic)
| |
| Interdimensional Sorcerer's Apprentice | | Chaosium Digest | v21n11 | Sep 1997 | Chaosium | Mythos
| |
| Inter-dimensional Transporter | Support (F) | The Twilight Beckons | CT40 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| The Interesting Shop | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| The Interesting Shop | Adventure (C) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Interface 19.40 | 51-55 | Interface 19.40 | MUH050027AC | 2015 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Interface Zero
, Savage Worlds (Achtung!)
| |
| Interim Period 1930-1931 | 51 | Coming Full Circle | PAG1003 | 1995 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Interim Period 1933-1934 | 83 | Coming Full Circle | PAG1003 | 1995 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Interim Period 1936-1939 | 107 | Coming Full Circle | PAG1003 | 1995 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| The Internet | Tome (C) | New Aeon | CAO1311-1 | 1997 | Chaosium | Mythos
| |
| INTERPOL Italian Headquarters | Location (C) | New Aeon | CAO1311-1 | 1997 | Chaosium | Mythos
| |
| Interrogation Center | Support (F) | The Spawn of the Sleeper | CT19 | 2009 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Interrogator | Character (F) | For the Greater Good | CT64 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Intersections | 166-226 | World War Cthulhu: Cold War | CB71970 | 2016 | Cubicle 7 | Call of Cthulhu (Cold War)
| |
| Interstellar Migration | Event (F) | The Key and the Gate | CT60 | 2013 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Interstellar Visitor | Character (R) | Masks of Nyarlathotep | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Intervention | Event (F) | The Spoken Covenant | CT36 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Interviews with Larry DiTillio and Lynn Willis | 11-14 | The Masks of Nyarlathotep Companion (Limited) | 60-MONC-08 | 2016 | Sixtystone Press | None
| |
| Interviews with Larry DiTillio and Lynn Willis | 11-14 | The Masks of Nyarlathotep Companion (Unlimited) | 60-MONC-03 (?) | 2016 | Sixtystone Press | None
| |
| Intimate Encounters | 122-135 | The Things We Leave Behind | TTWLB | 2016 | Stygian Fox | Call of Cthulhu (Now)
| |
| Intimidate | Event (C) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Intimidate | Event (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Intimidate | Event (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Intimidate | Event (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Intimidate | Event (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Intimidate | Event (F) | Secrets of Arkham | CT32 | 2010 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Into a Dark Heart | | Into a Dark Heart | | Aug 2021 | Chaosium | Call of Cthulhu (Classic)
| |
| Into the Darkness | | Tales of Terror (I) | | 1990 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Into the Darkness | 31-32 | Tales of Terror (III) | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Into the Darkness | 1990 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Into the Deep | Event (R) | Masks of Nyarlathotep | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Into the Depths | 178-195 | Assault on the Mountains of Madness | MUH050029 | 2013 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Into the East | 73-82 | Nocturnum: Deep Secrets | CC03 | 1999 | Fantasy Flight Games | Call of Cthulhu (Now)
| |
| Into the Fray | 159-170 | Keeper's Guide to the Secret War | MPS01032CS | 2013 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Into the Mouth of Truth | 49-67 | Shadows of Atlantis | MUH01022CS | 2015 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Into the Realm of the Wind-Walker | 59-72 | Walker in the Wastes | PAG1002 | 1994 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| Into the Throat of the Beast | 7-27 | The Arkham Evil | T-1 | 1983 | Theatre of the Mind Enterprises | Call of Cthulhu (Classic)
| |
| Into the Wilds, Into the Depths | | A Cold Fire Within | CHA23162 | 2019 | Chaosium | Call of Cthulhu (Classic)
| |
| Into the Woods | Conspiracy (F) | Lost Rites | CT56 | 2012 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| An Intriguing Offer | Support (R) | Eldritch Edition | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Introducing Call of Cthulhu Adventures | | Chaosium Digest | v24n03 | Mar 1998 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 24-34 | Call of Cthulhu | CHA23106 | 2005 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 23-35 | Call of Cthulhu | CHA2386 | 1999 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 4 | Call of Cthulhu 7th Edition Quick Start | CHA23131 | 2013 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 4-9 | De Profundis | CB71401 | 2010 | Cubicle 7 | De Profundis
| |
| Introduction | | Delta Green Anomalies | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| Introduction | 11-20 | Eldritch Skies | BPI7500 | 2012 | Battlefield Press | Unisystem (Eldritch Skies)
| |
| Introduction | 5-9 | Horror's Heart | CHA2359 | 1996 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 10-17 | Investigator's Handbook | CHA23136 | 2015 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 12-19 | Keeper Rulebook | CHA23135 | 2015 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 7-46 | Masks of Nyarlathotep | CHA23153 | 2018 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 4-6 | The Masks of Nyarlathotep Companion (Limited) | 60-MONC-08 | 2016 | Sixtystone Press | None
| |
| Introduction | 4-6 | The Masks of Nyarlathotep Companion (Unlimited) | 60-MONC-03 (?) | 2016 | Sixtystone Press | None
| |
| Introduction | 5-16 | Reign of Terror | CHA23149 | 2017 | Chaosium | Call of Cthulhu (Strange Aeons)
| |
| Introduction | 25-33 | Secrets of Japan | CHA2392 | 2005 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 9-30 | Skirmish: Commander's Set | MUH050454 | 2016 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Introduction | 4-19 | Terror from the Skies | CHA23128 | 2012 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction | 4-23 | World War Cthulhu: Cold War | CB71970 | 2016 | Cubicle 7 | Call of Cthulhu (Cold War)
| |
| Introduction | 4-8 | World War Cthulhu: Cold War - Our American Cousins | CB71973 | 2017 | Cubicle 7 | Call of Cthulhu (Cold War)
| |
| Introduction | 4-7 | World War Cthulhu: London | CB71941 | 2016 | Cubicle 7 | Call of Cthulhu (WWII)
| |
| Introduction | 8-19 | World War Cthulhu: The Darkest Hour | CB71939 | 2013 | Cubicle 7 | Call of Cthulhu (WWII)
| |
| Introduction | 1-5 | Zero Point, Part 3 - Code of Honour | MUH051257 | 2017 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Introduction and Orientation | 8-18 | Tatters of the King | CHA23104 | 2006 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction to 10th Century France | 21-34 | The Abbey | CHA0088 | 2004 | Chaosium | Call of Cthulhu (Dark Ages)
| |
| An Introduction to 1920s Scotland | 5-28 | Shadows Over Scotland | CB7353 | 2011 | Cubicle 7 | Call of Cthulhu (Classic)
| |
| Introduction to the Game | 9-13 | Lovecraftesque | | 2016 | Black Armada | Lovecraftesque
| |
| Introduction: Gazing into the Dark Mirror | 2-3 | Dark Mirror | CHA0338 | 2007 | Chaosium | Call of Cthulhu (Classic)
| |
| Introduction: The Storm | 3-12 | Children of the Storm | CHA0394 | 2010 | Chaosium | Call of Cthulhu (Classic)
| |
| The Intruder Beyond Time | Feb 2018 | Reckoning of the Dead | | n/a | Self Published | Call of Cthulhu (Now)
| |
| Intruder from Beyond | Character (F) | The Twilight Beckons | CT40 | 2011 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| The Intruder Within | | The Intruder Within | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Invasive Procedures | 4-35 | Invasive Procedures | PELG09 | 2011 | Pelgrane Press | Fear Itself
, Trail of Cthulhu
| |
| Inventor of Strange Devices I | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Inventor of Strange Devices II | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Inventor of Strange Devices III | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| Investigating Postergeists | 33-40 | Parapsycologist's Handbook | CHA0085 | 2003 | Chaosium | Call of Cthulhu (Classic)
, Call of Cthulhu (Gaslight)
, Call of Cthulhu (Now)
| |
| Investigating the Fate | 92-93 | Delta Green Eyes Only | PAG1013 | 2007 | Pagan Publishing | Call of Cthulhu (Delta Green)
| |
| The Investigation * | 89 | Taint of Madness | CHA2354 | 1995 | Chaosium | Call of Cthulhu (Classic)
| |
| Investigative Abilities | 29-33 | The Apocalypse Machine | PELGT24 | 2011 | Pelgrane Press | Trail of Cthulhu
| |
| Investigative Abilities | 30-34 | Cthulhu Apocalypse | PELGT40 | 2015 | Pelgrane Press | Trail of Cthulhu
| |
| Investigative Abilities | 4-37 | Keeper's Resource Book and Screen | PELGT04 | 2008 | Pelgrane Press | Trail of Cthulhu
| |
| Investigative Feats | 128-129 | Worlds of Cthulhu | 2 | Feb 2005 | Pegasus Press | Call of Cthulhu (d20)
| |
| Investigative Horror in the Dark Ages | 98-105 | Cthulhu Dark Ages | CHA23143 | 2015 | Chaosium | Call of Cthulhu (Dark Ages)
| |
| Investigative Reporter | Character (U) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| The Investigator | 9-50 | Player's Guide | PELGT03 | 2007 | Pelgrane Press | Trail of Cthulhu
| |
| The Investigator | 9-50 | Trail of Cthulhu | PELGT01 | 2007 | Pelgrane Press | Trail of Cthulhu
| |
| Investigator Archetypes for Zgrozy | | Investigator Archetypes for Zgrozy | | Oct 2019 | Chaosium | Call of Cthulhu (Classic)
| |
| Investigator Creation | 6-26 | Cthulhu Dark Ages | CHA23143 | 2015 | Chaosium | Call of Cthulhu (Dark Ages)
| |
| Investigator Domain 1 | Domain (F) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain 1 | Domain (F) | Eldritch Edition Premium Starter Set | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain 2 | Domain (F) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain 2 | Domain (F) | Eldritch Edition Premium Starter Set | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain 3 | Domain (F) | Arkham Edition | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain 3 | Domain (F) | Eldritch Edition Premium Starter Set | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain I1 | Domain (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain I2 | Domain (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain I3 | Domain (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain M1 | Domain (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain M2 | Domain (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Domain M3 | Domain (F) | Arkham Edition Premium Starter Set | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Investigator Expansion Pack | | Investigator Expansion Pack | | 2020 | Purple Meeple Games | Cultistorm
| |
| Investigator Occupations | 25-42 | The 7th Edition Guide to Cthulhu Invictus | GGP1801 | 2018 | Golden Goblin Press | Call of Cthulhu (Invictus)
| |
| Investigator Organizations | 122-145 | Investigator's Handbook | CHA23136 | 2015 | Chaosium | Call of Cthulhu (Classic)
| |
| Investigator Passports | 1-6 | Investigator Passports | | 2019 | base113 Games | Call of Cthulhu (Classic)
, Trail of Cthulhu
| |
| Investigator Promo Cards | | Investigator Promo Cards | | 2017 | Fantasy Flight Games | Elder Sign
| |
| Investigator Skills | 43-48 | The 7th Edition Guide to Cthulhu Invictus | GGP1801 | 2018 | Golden Goblin Press | Call of Cthulhu (Invictus)
| |
| Investigator Templates | 76-81, 45 | The Black Seal | 2 | Mar 2003 | Brichester University Press | Call of Cthulhu (Now)
| |
| Investigators | | Chaosium Digest | v01n04 | Feb 1993 | Chaosium | Call of Cthulhu (Classic)
| |
| The Investigators | 74-76 | Cthulhu Apocalypse | PELGT40 | 2015 | Pelgrane Press | Trail of Cthulhu
| |
| Investigators | 70-89 | Cthulhupunk | SJG01695 | 1995 | Steve Jackson Games | GURPS (CthulhuPunk)
| |
| The Investigators | 6-8 | The Dead White World | PELGT19 | 2011 | Pelgrane Press | Trail of Cthulhu
| |
| Investigators | | Investigators | | 2019 | Petersen Games | Cthulhu Wars
| |
| Investigators and Skill Progression | | Chaosium Digest | v17n09 | Dec 1996 | Chaosium | Call of Cthulhu (Classic)
| |
| Investigators as Tome Authors | | Chaosium Digest | v23n02 | Feb 1998 | Chaosium | Call of Cthulhu (Classic)
| |
| The Investigator's Gazeteer | 58-72 | Kingdom of the Blind | CHA0359 | 2008 | Chaosium | Call of Cthulhu (Classic)
| |
| Investigator's Guide to 1920s New Orleans | 9-26 | Tales of the Crescent City | GGP1401 | 2014 | Golden Goblin Press | Call of Cthulhu (Classic)
| |
| Investigators in the Holy Land | 5-10 | Dark Crusades | CHA0414 | 2013 | Chaosium | Call of Cthulhu (Dark Ages)
| |
| Investigator's Resources | 24-62 | World War Cthulhu: Cold War | CB71970 | 2016 | Cubicle 7 | Call of Cthulhu (Cold War)
| |
| Investigator's Resources | 20-52 | World War Cthulhu: The Darkest Hour | CB71939 | 2013 | Cubicle 7 | Call of Cthulhu (WWII)
| |
| Invisible Sun | 20-67 | Lost in the Lights | 60-NUK01 | 2013 | Sixtystone Press | Call of Cthulhu (Classic)
, Call of Cthulhu (Now)
| |
| The Invitation | 2004 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| An Invitation in Yellow | | An Invitation in Yellow | | Feb 2018 | Chaosium | Call of Cthulhu (Classic)
| |
| Invitation to Play | 9-19 | Serendipity's Circle | 6 | Win 1995 | Self Published | Call of Cthulhu (Now)
, Immortal: The Invisible War
, Nephilim
, The Whispering Vault
| |
| Invitation to the Dance | 19-38 | The Primal State | CHA0344 | 2007 | Chaosium | Call of Cthulhu (Classic)
| |
| Invitation to the Dance | 16-23 | The Whisperer | 5 | Aut 2003 | Severn Valley Press | Call of Cthulhu (Now)
| |
| Invocation of the Abyss | Event (F) | The Mark of Madness | CT66 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| The Involuntary Witness * | 80 | Taint of Madness | CHA2354 | 1995 | Chaosium | Call of Cthulhu (Classic)
| |
| Io | 20-22 | Jovian Nightmares | CHA0367 | 2009 | Chaosium | Call of Cthulhu (Rising)
| |
| Iod | Character (F) | For the Greater Good | CT64 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Ipiutak | Support (F) | Seekers of Knowledge | CT59 | 2012 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Ira Incensa | | Ira Incensa | | Mar 2021 | Chaosium | Call of Cthulhu (Classic)
| |
| Iranon the Explorer | Ally (C) | Dreamlands | CAO1307-1 | 1997 | Chaosium | Mythos
| |
| Irem | Location (F) | Antarctica | | n/a | Self Published | Mythos
| |
| Irem | Support (F) | The Sleeper Below | CT63 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Irem, City of the Pillars | Support (R) | Forgotten Cities | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Irish Channel | Support (F) | The Thousand Young | CT65 | 2015 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Irish Creatures of Legend | 44-50 | Mysteries of Ireland | CHA0408 | 2012 | Chaosium | Call of Cthulhu (Classic)
| |
| Iron | 95-123 | The Keeper's Companion Vol 2 | CHA2395 | 2002 | Chaosium | Call of Cthulhu (Classic)
| |
| The Iron Crib | 2001 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| The Iron Cross | Support (F) | Terror in Venice | CT61 | 2013 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| The Iron Ghost | 17-29 | Fearful Passages | CHA2335 | 1992 | Chaosium | Call of Cthulhu (Classic)
| |
| The Iron-Banded Box | 124-144 | Strange Aeons II | CHA23117 | 2009 | Chaosium | Call of Cthulhu (Strange Aeons: Sengoku period Japan)
| |
| Ironmind | Spell (R) | Dreamlands | CAO1307-1 | 1997 | Chaosium | Mythos
| |
| Irrational Express | | Irrational Express | | 2003 | Self Published | Call of Cthulhu (Now)
| |
| Irrational Means | Support (U) | Masks of Nyarlathotep | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Irregular Warfare | 59-80 | World War Cthulhu: The SOE Handbook | CB71942 | 2015 | Cubicle 7 | Call of Cthulhu (WWII)
| |
| Irresistable Allure | Event (P) | Arkham Edition Promo | | 2004 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| IRS Auditor | Event (U) | New Aeon | CAO1311-1 | 1997 | Chaosium | Mythos
| |
| Is Nothing Sacred | | GM | 18 | Feb 1990 | Croftward Limited | Call of Cthulhu (Classic)
| |
| Is This Heaven? | 66, 68 | Shadis | 19.5 | Jun 1995 | Alderac Entertainment Group | Call of Cthulhu (Classic)
| |
| Isaac Miles | Character (F) | Denizens of the Underworld | CT62 | 2014 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| The Island | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| The Island | | The Island | SKP01110 | 2011 | Skirmisher Publishing | Call of Cthulhu (Classic)
| |
| The Island | | Tales of Terror (I) | | 1990 | Pagan Publishing | Call of Cthulhu (Classic)
| |
| The Island | 20-21 | Tales of Terror (III) | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| The Island | 1990 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| Island 256 | | Island 256 | | May 2019 | Chaosium | Call of Cthulhu (WWII)
| |
| Island Approach | 00:32 | Eternal Lies Suite | PELGT17 | 2010 | Pelgrane Press | Trail of Cthulhu
| |
| Island Hermit | Character (F) | Ancient Horrors | CT17 | 2008 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| An Island Near the Equator | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| The Island of Splendour | 246-277 | Shadows of Atlantis | MUH01022CS | 2015 | Modiphius Entertainment | Call of Cthulhu (Achtung!)
, Savage Worlds (Achtung!)
| |
| Island of the Damned | 5-26 | Caligo Accendendum Tournament | CHA0309 | 2004 | Chaosium | Call of Cthulhu (Dark Ages)
| |
| The Island of the Dead | | Chaosium Digest | v05n11 | Feb 1994 | Chaosium | Call of Cthulhu (Classic)
| |
| The Island Paradises | 11-43 | The Bermuda Triangle | CHA2372 | 1998 | Chaosium | Call of Cthulhu (Now)
| |
| The Islands | 107-135 | Shadows Over Scotland | CB7353 | 2011 | Cubicle 7 | Call of Cthulhu (Classic)
| |
| The Isle of Dread | Adventure (F) | Eric Johnson Mythos Collection | | n/a | Self Published | Mythos
| |
| Isle of Lost Souls | 185-245 | Shadows of War | CHA0349 | 2008 | Chaosium | Call of Cthulhu (WWII)
| |
| Isle of Madness | | Isle of Madness | | Dec 2017 | Chaosium | Call of Cthulhu (Classic)
| |
| Isle of the Damned | | The Grindhouse Volume 1 | | Sep 2021 | Chaosium | Call of Cthulhu (Strange Aeons: 1974)
| |
| The Isles of Shoals and Other Innsmouth Inspiration | 26-30 | The Arkham Gazette | 2 | Nov 2013 | Sentinel Hill Press | Call of Cthulhu (Classic)
| |
| Isolated Town | Jul 2009 | talesofterror.net | | n/a | Self Published | Call of Cthulhu (Classic)
| |
| It Came From Beyond | Adventure (F) | Eric Johnson Mythos Collection | | n/a | Self Published | Mythos
| |
| It Came From Beyond | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| It Came from RKO Pictures | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| It Does a Body Good | 2018 | The Fairfield Project | | n/a | Self Published | Call of Cthulhu (Delta Green)
| |
| It Never Happened! | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
| |
| It Opens Doors | Nov 2019 | Reckoning of the Dead | | n/a | Self Published | Call of Cthulhu (Now)
| |
| Ithaqua | Monster (C) | Limited | CAO1300-1 | 1996 | Chaosium | Mythos
| |
| Ithaqua, The Killing Cold | Character (R) | Forgotten Cities | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
| |
| Itinerant Hotel | | Itinerant Hotel | | May 2021 | Chaosium | Call of Cthulhu (Classic)
| |
| Itinerant Scholar | Character (F) | Call of Cthulhu The Card Game | CT18 | 2008 | Fantasy Flight Games | Call of Cthulhu LCG
| |
| Itinerant Scholar | Character (U) | Masks of Nyarlathotep | | 2005 | Fantasy Flight Games | Call of Cthulhu CCG
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| It's Bedlam in Here! | 36-38 | The Unspeakable Oath | 5 | May 1992 | Pagan Publishing | Call of Cthulhu (Gaslight)
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| Its Full Of Stars! | Event (R) | New Aeon | CAO1311-1 | 1997 | Chaosium | Mythos
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| IT's in the Cards | 30 | The Whisperer | 1 | Sum 1999 | Severn Valley Press | Mythos
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| IT's in the Cards | 32 | The Whisperer | 4 | Spr 2001 | Severn Valley Press | Mythos
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| It's Just My Imagination | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
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| It's Plantlife Jim, but not as we know it, Part 1 | | Chaosium Digest | v38n02 | Nov 2003 | Chaosium | Call of Cthulhu (Classic)
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| It's Plantlife Jim, but not as we know it, Part 2 | | Chaosium Digest | v38n03 | Nov 2003 | Chaosium | Call of Cthulhu (Classic)
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| It's Real, I Know It Is | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
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| It's the End of the World as We Know It | Adventure (F) | House of Tindalos | | n/a | Self Published | Mythos
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| It's the End of the World As We Know It | 68-71 | Miskatonic University | CHA2352 | 1995 | Chaosium | Call of Cthulhu (Classic)
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