STRAIN

STRAIN is a 32-level partial conversion released in 1997 by the Alpha Dog Alliance. It features nine new or modified monsters, and a soundtrack written by David "Tolwyn" Shaw, Mark Klem, and Jon Landis.

New Weapons
The basic shotgun has modified artwork and sounds as a "sawn off shotgun". The plasma rifle is replaced with the NFG, which does much more damage per shot, and the BFG-9000 replaced with the Psychic Blaster, which fires stealth BFG-type shots lacking the after-effect of a BFG-9000 plasma burst, but with a limited range of rocket-type splash damage. The NFG and Psychic Cannon share cells, of which the player can have 50 maximum(100 after finding a backpack). The Psychic Cannon uses 3 cells per shot.

New Monsters
Usage of new tiles and DEHACKed editing creates several new monsters for the game-


 * Imps which move much faster and throw fireballs in a rapid manner. They have no visual distinction from normal Imps(which are in the WAD) but have a higher-pitched alert noise. They will literally run in a player's face faster than can be seen and are hard to target due to their speed. They take slightly more damage as well.
 * Demons are now red and take slightly more damage(on ITYTD a super shotgun blast will kill in one shot, assuming all 20 pellets connect).
 * Flying drones replace the Revenant gaining a Cacodemon-like hover ability. They fire both types of Revenant missile, both fo which travel at roughly half the normal speed and are much easier to dodge. They can also be found stealthed much like the Spectre.
 * Lost Souls now have blue and red flames with longer horns, and in addition to the standard ramming attack, now fire Imp fireballs.
 * Cyberdemons are now half normal size with higher-pitched alert and walking sounds. They take roughly 4-6 rockets to kill on ITYTD difficulty, but still fire normal rockets themselves, offsetting the comical idea of a miniature cyberdemon.
 * Presumably replacing the Spider Mastermind are flying cubes(taking grapics form the Icon of Sin's enemy spawn cubes). Their alert sound is a human voice saying "Got Him!". They fire the Spider Mastermind's chain shotgun.
 * The Mancubus is replaced by a superchaged Baron of Hell, with gray skin and green legs. They toss five green plasma balls at once in a spread pattern.
 * Certain zombie troopers fire off BFG-9000 rounds in later levels. There is no visual distinction between normal and BFG troopers until they fire.
 * Chaingunners have a new graphic set wearing the Marine helmet. The player sprite uses the same sprite set.
 * Cacodemons, Hell Knights and Barons of Hell toss their projectiles much faster

Levels
First "episode": Second "episode": Third "episode": Final "episode": Secret levels:
 * MAP01: Barracks by Bill McClendon
 * MAP02: Outskirts by Bjorn Hermans
 * MAP03: Downtown by Florian Helmberger
 * MAP04: Industrial Zone by Adam Windsor
 * MAP05: Depot by Jon Landis
 * MAP06: Launch Control by Jon Landis
 * MAP07: En Route by Adelusion
 * MAP08: Hangar by Rich Johnston
 * MAP09: Cargo Bay by Adelusion
 * MAP10: Entryway by Charlie Patterson
 * MAP11: Command Control by Bill McClendon
 * MAP12: Power Station by Bill McClendon
 * MAP13: Ruins by David Rotramel
 * MAP14: Engineering by David Graves, Adelusion, Rich Johnston, and Arthur Chang
 * MAP15: Subsidiary Power by Chainsaw
 * MAP16: Living Quarters by Charlie Patterson and Eric Roberts
 * MAP17: Promenade by Holger Nathrath and Arthur Chang
 * MAP18: Relay Station by David Rotramel
 * MAP19: Waste Processing by Darrell Esau
 * MAP20: Reactor by David Davidson
 * MAP21: Maintenance by Adelusion and Arthur Chang
 * MAP22: Specimen Storage by Adelusion
 * MAP23: Dispensary Alpha by Adelusion
 * MAP24: Sub-Laboratory by Adelusion
 * MAP25: Main Laboratory by Arthur Chang
 * MAP26: Main Laboratory II by Holger Nathrath, Charlie Patterson, and Eric Roberts
 * MAP27: Dispensary Beta by Andy Badorek
 * MAP28: Unknown by Bjorn Hermans
 * MAP29: Self-Destruct by Ron Allen
 * MAP30: Boss by Jon Landis and Rich Johnston
 * MAP31: Secret by Jon Landis
 * MAP32: Super-Secret by Holger Nathrath and Adelusion

Other Notes
Level 07 "En Route" seems to be impassible when played in ZDoom as the final exit does not function properly under the port. The WAD also has problems with the DEHACKed patch in Doom Legacy.