Cthulhu: An Unspeakable Mod is a Half-Life (1998) Game Mod, based on the Cthulhu Mythos. You play as Ranulf Stafford. Ranulf is an occult investigator who has been having bad dreams recently. Dreams of a sunken island resurfacing, and men awakening an evil of proportions no man can comprehend.
One evening, he visits his old friend Sir Henry, only to find a letter from Henry himself, that says that he has gone to his church. Ranulf decides to search for him there, and that is when the journey starts - pulled into the madness that is the knowledge of the Great Old Ones, Ranulf must investigate a cult planning to awaken Cthulhu.
Cthulhu: An Unspeakable Mod provides examples of the following tropes:
- Absurdly Spacious Sewer: The one below the City of Yith.
- Alien Geometries: The City of Yith is full of it.
- Apocalyptic Log: Many pages written by cultists, scientists and Henry are found in the mod.
- Artifact of Doom: You read the Necronomicon in the library. Immediately afterwards, enemies attack.
- Cassandra Truth: no one believes Ranulf when he returns from R'Lyeh after saving the world, and thus he is locked up in Arkham Asylum.
- Chest Burster: A man lying in a bed screams and then die. Then small spiders burst out of his body.
- Cosmic Horror Story
- Corrupt Church: The Black Church. Full of chanting cultists.
- Cult: The Esoteric Order of Dagon.
- Did You Just Romance Cthulhu?: Dr Whately gave Yog-sothoth his wife. The small spiders you have been fighting the whole time have been the offspring.
- Dreaming of Things to Come: Ranulf dreams of the Esoteric order awakening Cthulhu before the game starts.
- Driven to Suicide: Dr. Whately, who created the monsters in Dunwich, is found dead with a knife and a note explaining it.
- Eldritch Abomination: Cthulhu and Dagon.
- Eldritch Location:
- The island above R'lyeh.
- You also go Millions of years back in time to the City of Yith.
- Enemy Chatter: "The stars are almost right..."
- Evil Laugh: One of the cultists does one, After Ranulf has been locked in the asylum. They are now free to awake Cthulhu again.
- Exclusive Enemy Equipment:
- The Thompson is only gained by picking it up from a dead Mobster later on in the game.
- The cultists are carrying daggers that you can only get by killing them.
- Fish People: The Deep Ones.
- Game Mod
- Human Sacrifice: Ranulf witnesses a man dying being dropped from a cage into a well, filled with acid.
- Immune to Bullets: The scientists experiments that can only be killed by fire or magic. Also, Cthulhu.
- Invisible Monsters: the Spawn of Yog-sothoth.
- Jump Scare: Most of them in The Ghoul's Lair. The caves are small and narrow with sharp turns, so you might often end up in front of one of the Ghouls.
- Justified Tutorial: Since most people should already know about moving and firing in a gold source game, the hazard course simply consists of visiting Sir Henry. Then he explains how the powers of the spellbooks work.
- Kill It with Fire: Father Dagon, and some other enemies, are weak against fire.
- Laser Hallway: Ranulf wanders into one in Yith. Fortunately, there is a grid on the floor that he jumps through, surviving the trap.
- Life Drain: The Spellbook of the name Drain Life can do just that from human enemies.
- Loads and Loads of Loading: The maps are smaller than the usual, which means then leaving an area might load again and again. Thankfully, they are still only a few seconds long, as in most Half-Life mods.
- Lovecraft Country
- Molotov Cocktail: One of the useful weapons obtained.
- More Dakka: The Thompson gun gets a lot of ammo while visiting the lair of the Mob.
- Names to Run Away from Really Fast: Every area in the game really. Innsmouth, Dunwich, Ghouls Lair, City of Yith, R'lyeh...
- New Work, Recycled Graphics: In many places. Most notably in R'lyeh, you encounter Shock Troopers from Opposing Force more or less unchanged. They're presumably supposed to be Cthulhu's star spawn. Cthulhu himself, meanwhile, uses a sized-up and modified Gargantua model.
- Occult Detective: Ranulf Stafford.
- Ominous Fog: Innsmouth is sweept in one.
- Organic Technology
- Our Ghouls Are Creepier: The way that leads into their lair might be in a graveyard, but ghouls are neither demons or undead.
- Paranormal Investigation
- Sanity Meter: Using the magic attacks costs the sanity of Ranulf. When it reaches zero it's game over, and it can only be refilled by defeating the bigger enemies in the mod.
- Spell Book: Weapons which Ranulf hold while casting the different spells.
- Spooky Silent Library
- Standard FPS Guns: And some not so standard.
- Starfish Aliens
- Stealth Pun: The icon that represents the sanity meter on the hud is a small picture of Howard Philips Lovecraft. You get HP for defeating bosses.
- Sword Cane: The first weapon is one, found in Sir Henrys Wisdom church.
- The Blank: The Night Gaunts. Though it is hard to see since it is so dark in the areas around the Church.
- The Mafia: The Finucciaro family.
- The Roaring '20s
- Town with a Dark Secret: Innsmouth.