Characters that can mimic humans perfectly, but their speech is a dead giveaway that they're a mimic

Fleshcousin (Roblox Regretevator) - will mimic the appearance of a random player upon reaching it's floor, but all it's dialogue is total nonsense

The Serverblight (SERVERBLIGHT) - Mimics Hector0n (after presumably assimilating him) in order to trick and assimilate dicksalot, however it can only use voice clips a player has said before, and has trouble displaying the voice chat icon correctly

Nothing There (Lobotomy Corporation) - Can steal the skins of Agents if they die in its chamber, allowing it to mimic them, however when disguised it will frequently say "I love you"