Deconstruction: DOOM - Part VI: Enemies

In DOOM, there are only ten enemy classes, but most of them offer a unique feature that can make them either challenging or helpful.

The two helpful enemies are Former Humans and Former Human Sergeants.  These two enemies are zombies that fire pistol rounds or shotgun shells, respectively, and after killing them, ammo for the gun they used can be picked up.

Imps, Barons of Hell, Cyberdemons, and Spiderdemons are all simple enemies that fire projectiles.  Imps are standard enemies, Barons of Hell are bosses at the end of Episode 1, although they become standard enemies or minibosses later on, a Cyberdemon is the boss of Episode 2, and Spiderdemons are bosses of Episodes 3 and 4.

He told you he was a boss.  He lied to you.

Demons do not have projectiles, but instead run at the player and bite.  Spectres are demons that are "cloaked" the way the Predator cloaks in the Predator movie franchise.  The look to these enemies is similar to when the player character grabs an Invisibility powerup.

Cacodemons fire projectiles, but float, so that they are not restricted by ledges or walls.

Lost Souls take from both Demons and Cacodemons, in that they float, but have no projectiles.  Instead they act as the projectile by charging at the opponent.  The similarity to a projectile was not lost on the id staff, and in fact, by Doom II they become a new enemy's projectile.

These are all the enemies in DOOM.  They are a short list of seven standard enemies, one miniboss, and two bosses.

However, the main innovation in DOOM about enemies is not their individual traits, but how they act with each other.  Enemies of the same class, for the most part, band together to destroy you.  When there are enemies of more than one class in the same room, if one accidentally hits another one with a projectile, they will turn against each other and you can find a safe spot and watch the fight.

The two Human classes and Lost Souls take this a step further, and will kill members of their own class, as well.

This feature means that when level designers place enemies, they have to be careful about which type of enemies they want and how many.  If enemies of different classes are in the same room, but there are few of them, the likelihood of an enemy-on-enemy brawl is not likely, because they don't get in each other's way.  But if, say, a Demon or two is charging at the player, and Imps are lobbing fireballs from the back line, odds are the Demons are going to get hit, turn around, and go after them.

On some occasions, the designers carefully placed enemies like this so this would happen.  In DOOM II, for instance, MAP08:  Tricks and Traps has a room with one Cyberdemon and a ton of Barons of Hell.  The Barons are facing away from the player, but the Cyberdemon sees the player immediately.  The Cyberdemon is placed at the far end of the room, so the Cyberdemon will start firing rockets at the player, hitting the Barons, and all Hell breaks loose.

This "brawl" feature allows the player to conserve ammo and avoid confrontation, and can be used in many situations, although it can often be tough to pull off.  Running between enemies and hoping they accidentally shoot each other is a tricky maneuver, and the results can be disastrous if misjudged.

Read Part VII: Difficulty