History VideoGame / TouhouDoom

* BonusBoss: Like in ''Touhou'', the Extra bosses (Flandre, Koishi, Yukari, and [[spoiler:a refight against Mephistopheles]]) are completely optional. There's also [[spoiler:[[VideoGame/{{Ketsui}} Evaccaneer DOOM]]]], accessible by completing five secret challenges during the fourth episode, Maps 21-25, and completing the 4th episode's Extra Stage.

* SmartBomb: The various spellcards you can collect fill this role, acting as the replacement for the {{BFG}} in Episode 2 and onward. You can even use them to destroy enemy projectiles coming right at you in true Bullet Hell fashion.

''Touhou Doom: Unusual Invasion of Fire and Brimstone'' is a 5-episode, 32-map megawad for ''Videogame/DoomII'' created by Untitled made for the [=GZDoom=] engine that combines the gameplays of ''Franchise/{{Touhou}}'' and ''VideoGame/{{Doom}}''.

''Touhou Doom: Unusual Invasion of Fire and Brimstone'' is a 5-episode, 32-map megawad for ''Videogame/DoomII'' created by Untitled made for the [=GZDoom=] engine that combines the gameplay of ''Franchise/{{Touhou}}'' and ''Doom''.

''Touhou Doom: Unusual Invasion of Fire and Brimstone'' is a 5-episode, 32-map megawad for ''Doom 2'' created by Untitled made for the [=GZDoom=] engine that crosses over the gameplay of ''Touhou'' with that of ''Doom''.

*** Praise Benellus! is a reference to Benellus, the God of Shotguns, with the attacks stole directly from his appearance in ''Dump 3'', which Untitled had made a map for.

*** Praise Benellus! is a reference to Benellus, the God of Shotguns, with all the attacks from his appearance in ''Dump 3'' (''Doom Upstart Mapping Project'') kept intact.

* GameMod: The [[https://forum.zdoom.org/viewtopic.php?f=43&t=58868 Touhou Doom Advance Pack]] adds in a scoring system, power and point items, extends, and grazing into the base mod. Untitled has also made a mod that allows you to play with the enemies and allies of the mod with any map set, which also includes a ''Touhou''-themed weapon set as well.

* CirclesOfHell: The [[spoiler:refight against Mephistopheles]] in Map29 uses the Circles of Hell from ''Literature/TheDivineComedy'' as the "theme" for his spellcards.

* ShoutOut: Koishi's second phase references a bunch of modders from the Doom community, that the creator has respect for:
** ''Shivers Sign 'Original Map Do Not Steal'' is a reference to the modder Sgt. Shivers, who made his own version of Touhou Doom based on an even older version made by modder [=DustedPandemonic=]. Dusted's version of Touhou Doom stole a map from Freedoom, so Shivers replaced that map with the iconic [=E1M1=] for his version.
** Dekw Sign 'This is why we can't have nice things' is a reference to the creator's brother, who was also the main tester of the mod. He was constantly finding bugs or exploits to break the game, which annoyed Untitled so much that he made this spellcard to spite him. This explains why the arena itself is a bland rectangular room.
** Yholl Sign "But they had A_SetScale" is a reference to the modder Yholl, who during a stream of the older Touhou Doom was happy when it was used, even if only once. Naturally, the attack doesn't use A_SetScale at all.
** Terminus Sign "Philosophy Of A Hated Candelabra" is a reference to modder [=TerminusEst3=], who played through the original version of Touhou Doom with his own ''VideoGame/{{Demonsteele}}'' mod. In ''Demonsteele'', you can destroy decorative items like candelabras, and Terminus vowed to break every single candelabra in the game. The bullets in this spellcard are actually blocked by the candelabras, so destroying them makes the spellcard harder to dodge.
** Praise Benellus! is a reference to Benellus, the God of Shotguns, with all the attacks from his appearance in ''Dump 3'' (''Doom Upstart Mapping Project'') kept intact.
* UnexpectedGameplayChange: Yukari's optional Phantasm stage and the first half of 'The One Who Opens The Gates' will change the gameplay to ''Touhou'''s top-down vertical scroller roots.

** ''Shivers Sign 'Original Map Do Not Steal'' is a reference to the modder Sgt. Shivers, who made his own version of Touhou Doom based on an even older version made by modder [=DustedPandemonic=]. Dusted's version of Touhou Doom stole a map from Freedoom, so Shivers replaced that map with [=E1M1=]
** Dekw Sign 'This is why we can't have nice things' is a reference to the creator's brother, who was also the main tester of the mod. He was constantly finding ways or bugs to break the game, which annoyed Untitled so much that he made this spellcard to spite him. This explains why the arena itself is a bland rectangular room.
** Yholl Sign 'But they had A_SetScale' is a reference to the modder Yholl, who during a stream of the older Touhou Doom was happy when it was used, even if only once. Naturally, the attack doesn't use A_SetScale at all.
** Terminus Sign 'Philosophy Of A Hated Candelabra' is a reference to modder [=TerminusEst3=], who played through the original version of Touhou Doom with his own ''VideoGame/{{Demonsteele}}'' mod. In ''Demonsteele'', you can destroy decorative items like candelabras, and Terminus vowed to break every single candelabra in the game. The bullets in this spellcard are actually blocked by the candelabras.

* ShoutOut: Koishi's second phase references a bunch of modder's from the Doom community, that the creator has respect for:

** Dekw Sign 'This is why we can't have nice things' is a reference to the creator's brother, who was also the main tester of the mod, but was still finding ways to break it, so this attack was made out spite.
** Yholl Sign 'But they had A_SetScale' is a reference to the modder Yholl, who during a stream of the older Touhou Doom was happy when it was used, even if only once. Yet the attack doesn't even use A_SetScale at all.
** Terminus Sign 'Philosophy Of A Hated Candelabra' is a reference to modder [=TerminusEst3=], who played through the original version of Touhou Doom with his own ''VideoGame/Demonsteele'' mod, which allowed him to destroy various light decorations, including candelabras, which he swore to destroy every single one of. The bullets in that spell cards are actually blocked by the candelabras.

** Shivers Sign 'Original Map Do Not Steal' is a reference to the modder Sgt. Shivers, who made his own version of Touhou Doom, based on older version, which had a map stolen from Freedoom, so for his version, Shivers stole Hangar from Doom, so Untitled stole that version.

** Terminus Sign 'Philosophy Of A Hated Candelabra' is a reference to a modder Terminusest, who played through original Touhou Doom with Demonsteele, which allowed him to destroy various light decorations, including candelabras. If you were to play this version with Demonsteele and destroy said candelabras, prepare for instant karma.
** Praise Benellus! is a reference to the final boss from the mapset DUMP 3 (Doom Upstart Mapping Project), who is the god of shotguns, with all the attacks kept in tact.

** Terminus Sign 'Philosophy Of A Hated Candelabra' is a reference to a modder Terminusest13, who played through original Touhou Doom with Demonsteele, which allowed him to destroy various light decorations, including candelabras. If you were to play this version with Demonsteele and destroy said candelabras, prepare for instant karma.

** Terminus Sign 'Philosophy Of A Hated Candelabra' is a reference to a modder TerminusEst13, who played through original Touhou Doom with Demonsteele, which allowed him to destroy various light decorations, including candelabras. If you were to play this version with Demonsteele and destroy said candelabras, prepare for instant karma.

** Shivers Sign 'Original Map Do Not Steal' is a reference to the modder Sgt. Shivers, who made his own version of Touhou Doom, based on older version, which had a map stolen from FreeDoom, so for his version, Shivers stole E1M1.
** DekW Sign 'This is why we can't have nice things' is a reference to the creator's brother, who was also the main tester of the mod, but was still finding ways to break it, so this attack was made out spite.

''Touhou Doom: Unusual Invasion of Fire and Brimstone'' is a 5-episode, 32-map megawad for ''Doom'' created by Untitled made for the [=ZDoom=] engine that crosses over the gameplay of ''Touhou'' with that of ''Doom''.

* MindScrew: Koishi's second phase is a reference to the ''Koishi Hell'' series of Danmakufu scripts that seek to make the most insane spellcards for her. These spellcards are all {{Development Gag}}s to the megawad's development
* UnexpectedGameplayChange: Yukari's optional Phantasm stage will change the gameplay to ''Touhou'''s top-down vertical scroller roots.