YMMV / Compound

• Demonic Spiders:
  • KANi Bots, which are appropriately spider-like in appearance, are small, possess tanky energy shields that take quite a bit of punishment, and are fairly hardy themselves, taking two direct Super Shotgun blasts to put down on Hard mode. At longer range, they shoot bullets at you while you're in line of sight. At close range, they drop their shields and lunge at you. By themselves, they're not too hard to dispose of - just wait until they get close by and drop their shield, then rinse them - but they almost always appear alongside other groups of enemies, throwing off your concentration. On Hard difficulty and above, all boss levels past the first one contain several that you have to take out, often hanging out in the same room and aggroing against you all at once. The one saving grace is their vulnerability to explosive weapons, which kills them in one direct blast even on Hard, especially the Sticky Launcher, whose sticky bombs, with the right timing, can be detonated under their shields. This can still be tricky to do, however, when faced with multiple at once, or with other enemies bearing down on you.
  • Stalkers, particularly the red-and-blue variant. Both are heavily-armored, but while the orange ones fire at you with rail gun rounds that take a minute to charge and can easily be sidestepped, the red-and-blue Stalkers constantly fire normal bullets with surprisingly-scary accuracy as long as you're in their line of sight, without ever needing to reload unlike normal guards.
• Goddamn Bats: Drones, especially the Pink ones that appear in the later levels. They only take one shot to defeat, but they have an erratic, unpredictable flight pattern which can throw off your aim easily, and the pink ones have a very scary high rate of fire that's all but guaranteed to nail you if you can't take them out quickly enough.
• That One Boss: On Hard mode and above, the Sewer Rat in Sewers 2, despite being the first mini-boss, is one of the most difficult in the game. It's an insane bullet sponge, moves quickly with a far-ranging vomit attack, and begins hunting you the second you first move in the map, likely crossing through a number of rooms and leaving mooks trailing behind him. It doesn't help that this is a time in the game when you only have one special weapon and limited ammo to fight him with.
  • Also on Hard mode and above, the Gold Leader found in Executive Power 2. He tanks quite a few hits, and is by far the fastest enemy in the game when you exit line of sight, sprinting to your position when he can't see you. At short range, he pelts you with hyper-accurate, quick shotgun blasts - if he corners you without cover and you can't kill him quickly enough, you're as good as dead. At long range, he holds up a similar energy shield to The Accountant, and fires at you with rail gun shots after a small delay, although this energy shield has a small opening on one of its corners. Unless you have a rail gun yourself, another long-range weapon or an explosive weapon to bypass his shield, you're in for a rough time.
  • As for non-Hard-exclusive bosses, Booster Bruce is probably the most aggravating. The second he gets aggroed, he darts towards you on his jetpack, spraying at you with his submachine gun. The layout of the Vaccine Warehouse can be taken advantage of against other enemies, but not Bruce, who gleefully flies over and around terrain and over damaging wall traps to catch up to you. And he will catch up to you. His erratic movement makes hitting him with explosives difficult, and his constant barrage of bullets can end your run if you get trapped in a bad spot and don't have powerful weapons to take him out quickly enough.
• That One Sidequest: Unlocking the Dart Gun requires beating the game with the 'Damage Amplifier' mutator in effect. All of your bullets become One-Hit Kills on every enemy, including bosses, but so do theirs to you. Unless you get lucky enough to find a helmet, you'll likely have to cautiously check every corner at a steady pace, and one bad spawn of a pink drone or a shotgun guard is all it takes to end your run, even on Easy difficulty.

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