From Quake Wiki
"Grunt, Mark Two. Grunts who are surlier and beefier than the rest get outfitted in combat armour and built-in blasters."
The Enforcer is the brute of the military base maps. You can tell them apart by their beefier build, helmets and backpack. Wielding a laser cannon with perfect aim, they fire in two shot bursts, ensuring that you have to step quickly to avoid harm. On death they will drop a backpack containing five cells.
Enforcers are the only Quake monster showing Earth human intelligence, as some of their sounds bear a strong resemblance to English words, typically used by guards of any sort. This suggests that in their strength, they were less assimilated as a whole by Quake's forces, and thus retained a bit more of their minds.
Interestingly, their uniform bears a strong resemblance to the Biosuit, which can be used as rationale for their underwater excursions in The Sewage System, though the Grunts doing the same are a mystery. Easy to be knocked into a pain frame, and lacking a melee attack, Enforcers are generally best dealt with by the Double-Barreled Shotgun as the normal one would be wasteful of shells, but the Nailgun can work well on a group.
Their projectile can also be found as an option for the trap_shooter entity, which can be seen used to an extreme extent in the first level of Beyond Belief where a tight cluster of them act as a security system to prevent the player from passing. Beyond Belief also modified the Enforcer to drop only two cells on death, making them less of a boon to the player at a later point upon finding the Thunderbolt.
"Player was blasted by an Enforcer"
|Monsters from Quake|
|Chthon | Death Knight | Enforcer | Fiend | Grunt | Knight | Ogre | Rotfish | Rottweiler | Scrag | Shambler | Shub-Niggurath | Spawn | Vore | Zombie|