YMMV / Luftrausers

• Demonic Spiders: The dreadnoughts. They can easily shoot across the map, their shots come in huge barrages with no penalty to their damage, they are as dangerous up-close as they are at long range, are really good at leading their shots to hit you even if you try to speed past them, they're durable enough that you can only easily take them on with the Cannon, and there's nothing to stop three or four of them from spawning at the same time. It gets worse in SFMT mode, since the gap between barrages is significantly reduced, meaning one - let alone several - can put up an impossible to navigate wall of fire. Four or more is simply impossible for most players.
  • Aces and Laseraces can be. The former is due to their manuverability matching you (though a good Rauser pilot will have little trouble dealing with them). The latter is due to their pinpoint-accurate laser weapon which is a copy of the Player's, spawning in pairs, and exploding in a dodgable - but only just - version of the Nuke body which fires a laser in nearly every direction when they die. In SFMT, Aces can spawn as regularly as regular fighters and also launch missiles on top of their normal guns.
• Game-Breaker: The Nuke body trivializes a lot of kill challenges, because thanks to your auto-self destruct that kills everything on-screen you don't even need to be alive to clear them.
• Scrappy Weapon: Missiles. Theoretically they're homing missiles, but their actual homing ability is piss poor (frequently you'll shoot a missile near an enemy, only for it to just fly off without even trying to track it) you can only fire four at a time, and you're anywhere near the water chances are they'll just veer off into the water and hit nothing.
  • The Gungine. Your regular engine is replaced with a slow-firing gun that propels you forward with each shot. As an engine, it's painfully weak, and as a weapon you're better off just turning around and shooting behind you.
• That One Achievement: The "kill 8 boats in one combo" missile challenge is an utter nightmare due to how the missiles' homing capabilities tend to give out if they go anywhere NEAR the water, leaving you better off just ramming into them and hoping the game spawns enough for you to keep your combo going.