Doom/Doom II/Final Doom
The Spiderdemon is not mentioned in the Doom manual, presumably to avoid a spoiler. Perhaps as a result of this, the manual for the Depths of Doom Trilogy erroneously states that it appears in Doom II only.
The Official Doom FAQ (included in Doom 1.4) describes the creature as a 'huge robotic chaingun shooting spider," adding "it will make you wish you never were playing DOOM in the first place. Watch for it at the end of the third episode of DOOM, and numerous times times in DOOM II."
The Doom II manual presents the Spider Mastermind as the mother of the Arachnotrons: "You guess the Arachnotrons had to come from somewhere. Hi, Mom. She doesn't have a plasma gun, so thank heaven for small favors. Instead, she has a super-chaingun. Crap."
Doom II RPG
The Spiderdemon is the second form of the Arachnotron class, and also a boss. It births three Arachnatrons upon death.
The Spider Mastermind serves as the final boss of the game, and is implied to be the commander of Hell's forces during the game's events. It is massively larger than before, with a bulkier body and a plethora of new attacks rather than just its original super-chaingun. It is implied to be the same Spider Mastermind fought in E3M8: Dis in the original Doom.
The creature is shown to manifest after Olivia Pierce is pulled down into the ground: this appears to be the process of merging described in the Codex entry, which is necessary for the creature to fully manifest itself. Whether Olivia still existed within the Spider Mastermind after it formed is unclear.
- The Spiderdemon is named as "Spider Mastermind" in The Ultimate Doom, Doom II, Final Doom and the Depths of Doom Trilogy's manual, as well as Doom II RPG.
- It is the final boss of the first Doom, and appears again in the final episode of The Ultimate Doom, Thy Flesh Consumed. The PlayStation and Saturn versions of Doom in turn feature two Spiderdemons as the bosses of its final level, Redemption Denied on harder skill levels. Olivia Pierce is transformed into a Spider Mastermind in Doom (2016).
- In the original Doom game, this monster is called just "Spiderdemon". However, in Doom II cast sequence it has the less generic name "The Spider Mastermind".
- Despite being the final boss, several attributes of the Spiderdemon are inferior to the Cyberdemon, such as hit points, speed and pain chance. Since they have different types of weapons, there is no objective way to tell which one is more powerful, as both monsters can sometimes take down one another as seen in one level. However, in favor of the Spiderdemon, its very wide hitscan make their attacks harder to avoid, while the Cyberdemon's rockets can easily be avoided by circlestrafing.
- While the Spiderdemon is considered more threatening and story-critical in the original Doom, in Doom II the Cyberdemon is given "higher billing" as the greater monster. The Spiderdemon is the last boss in Doom as well as in The Ultimate Doom's extra episode, Thy Flesh Consumed, and is credited with controlling the invasion of the Phobos and Deimos bases. However, in Doom II the Cyberdemon is the last monster fought in MAP29 before the actual final boss fight in MAP30, in addition to the Spider Mastermind appearing before the Cyberdemon in the endgame cast sequence.
- Upon death the Spiderdemon collapses into a heap, with an accompanying series of explosions. The Spiderdemon, along with the Demon, Mancubus, and Cyberdemon are the only monsters whose dying sound clips includes noise other than the monsters' vocals. As it collapses, frame-by-frame analysis shows that a piece of metal from its cybernetic portion pierces its forehead from within. Its mouth, complete with pointed teeth still intact, is visible on its otherwise ruined corpse.
- The Spiderdemon, Arachnotron, and Cyberdemon are the only monsters that constantly make sound when they walk.
- Near the beginning of MAP20 in Doom II, the player is given the opportunity to lure a Spider Mastermind and a Cyberdemon into battling each other via monster infighting. Unless a third party intervenes, the Cyberdemon usually wins.
- The easiest and safest way to get them to infight is by luring the Spider Mastermind into attacking the Cyberdemon first. Since the Cyberdemon's rockets are far easier to dodge than the Spider Mastermind's hitscan bullets, this helps weaken the Cyberdemon quicker by using him as a living shield. Regardless of which one is left standing, the surviving monster will be left in very little shape to face the player again. Whichever wins will almost certainly perish from a well-placed BFG blast, or failing that can be quickly dispatched with rockets or the plasma rifle.
- The sprites are different from the original latex and metal model, as seen here. The model has a 3-barrelled chaingun implanted right below the mouth, while the game sprites have a 6-barrelled chaingun implanted into the base.
- MAP28: The Spirit World in Doom II is the only level designed by id Software that includes more than one Spider Mastermind at the same time. Two appear near a group of Arachnotrons, on the "Hurt me Plenty", "Ultra-Violence", and "Nightmare!" skill levels.
- The Spiderdemon's "super-chaingun" uses the same sound clip as the shotgun, played repeatedly at a high speed. In addition, the attack uses the same spreading behavior as the Shotgun Guy's shotgun for each shot, making it in essence a rapid-fire shotgun attack.
- The PlayStation and Saturn ports' version of the Spiderdemon only contains one sound clip, used for both an alert sound and a dying sound.
- As with all hitscan attack monsters, it is possible for two Spiderdemons to infight each other. The only instances where this can happen in the official commercial levels is MAP28 of Doom II and in MAP54 of the PlayStation/Saturn ports.
- In a ZDoom-based source port, if the player is killed by a Spiderdemon (monster is credited with delivering the blow that reduces player's health to 0%), an obituary message is displayed at the top of the screen: "[player name] stood in awe of the Spider Mastermind".
- In Brutal Doom, the Spiderdemon begins attacking the instant it engages its target, and fires extremely powerful explosive rounds. Its mechanical chassis absorbs about 7/8th of the original damage value inflicted by any attacks, produces metal sparks (in case of a chainsaw attack), and deals shrapnel damage from gunfire attack. The monster's death sequence is enhanced to explode violently, dealing damage to anything caught in the blast - except for another Spiderdemon or a Cyberdemon.
- The Spider Mastermind is, in general, a rarely-encountered monster. The four commercial IWADs contain just fourteen between them on the highest difficulty level; by contrast, twenty-three Cyberdemons appear in Plutonia alone.
- Main article: Spider Mastermind (Doom II RPG)
In the Doom II RPG, the Spider Mastermind appears as the game's second boss.
- The Spiderdemon bears a conceptual resemblance to Krang from the 1987 edition of Teenage Mutant Ninja Turtles. Both pilot walking machines with the difference being that the Spiderdemon's machine is a much larger and a more generic-looking quadruped.
- In the 2012 Teenage Mutant Ninja Turtles series, there is the Kraang Spider Gunner, which seemingly completely parodies the Spider Mastermind.
- Both the Doom I and Doom II Official Strategy guides identify the Spider Mastermind as male.
- Doom 1.4 official FAQ