ce2317ef_Traits___Rogue_Legacy_Wiki__Effect
[Name] Dementia [Description] "You are insane!" [Effect] 
The player occasionally hears creepy laughter and noises. The player will also occasionally see enemies that don't "exist." Attacks from these enemies will do no damage, and the player cannot damage these enemies. Any attempts by the player to damage them will only result in question marks floating up from the enemy's head. Hallucinated enemies are sometimes from another part of the castle than you are currently in, and are always lowest-tier enemies, e.g. Corrupt Knight instead of Corrupt Vanguard or Corrupt Lord. This makes spotting hallucinations particularly easy in New Game+ modes.
Traits - Rogue Legacy Wiki
Effect