Weeping Angels
Link: Minecraft Forum
Weeping Angels are terrifying creatures made of stone that will follow you at night in an attempt to attack however if you manage to spot them, they will freeze to stone, that is until you wander away once again. These mobs are rare with a low spawn rate of about 5% and they are only available at night or within dark areas such as caves though they have been known to attack light sources in order to travel freely.
Inspired by the fictional alien race from Doctor Who, the Weeping Angels are menacing and can be tough to kill. Their attack can deal over three hearts of damage and there’s a chance they can teleport you up to 5,000 blocks away.