Realm of the Mad God/YMMV


 * Demonic Spiders: They have the hitbox of a bat and the stats of a Lightning Bruiser. Oh, and they fire annoyingly small green projectiles that blend into the background. The bats do them one better in the Manor of the Immortals, where they inflict the incredibly annoying Confused status, making it highly likely you'll stumble right into Nosferatu.
 * Fanon: Pretty much all of the game's lore is this.
 * Game Breaker: Some argue that the Spider Den dungeon makes it too easy to level up, as a single trip though the Spider Den can elevate a level 1 player to level 10.
 * The Spider Den no longer allows for quick level ups.
 * Up until the bug was fixed, the best healing spell actually fully healed everyone on the entire map. One maxed priest could drop two or three of them before having to drink mana potions.
 * Goddamned Bats: Small, quick, can't be killed in a single hit, deal just enough damage to be annoying.
 * Memetic Mutation: Just about everything related to the Mook Maker-spawning Mook Maker CUBE GOD.