Stalker

Stalker is an aggressive melee mob found in Dustopia.

Spawning
Stalkers spawn naturally in Dustopia.

They will despawn if the player gets too far away from them, or if the difficulty is set to Peaceful.

Behavior
Stalkers are melee mobs that will follow targets both on land and in water. They will initially attempt to avoid getting into the water where possible, but will go in if they find no other path to their target.

They are aggressive, and will attack nearby players within 16 blocks without provocation. If attacked by another entity, they will retaliate and continue targeting that entity.

Looking at a Stalker within 2 blocks will cause a static effect on the screen. Additionally, Stalkers will teleport away from the player if they are hit.

Staying outside of their targeting range will prevent them from attacking or targeting entities.

Trivia
This mob idea most likely came from Slenderman, the main antagonist in the game Slender.