Parasite

Parasite is a humanoid "Creature" found at room 550, he is pale, wearing ragged clothing and appears to be wearing some sort of mask on his head. He is encountered after exiting the vents. He drains a whopping 60% of health on hit, this means that he can 2 shot you but luckliy he is very slow, however his ability is that moving too far away from him will cause him to enrage, entering a speed faster then a sprinting player. Upon hitting someone they will become calm again. If you try to enter a room with him enraged, he will enter the room enraged.

Tips
Do not make a run for it. if you do and then enter a new room, it will enrage anyways.

Try to learn to not panic, most people start running away after being hit, which results in the parasite getting enraged and finishing them off.

Learn what music he plays when chasing you, so that you don't forget that its the parasite and should'nt be running.

Hard mode changes
In hard mode, he gains one of the most annoying but adaptable ability, he gets the ability to become fully invisible unless he is enraged, however you can hear loud static noises around him, meaning you will have to use audio to track him down. You can't run away either because of the enrange mechanic, however once you get used it to you will be able to easily escape him.

Trivia
Parasite is inspired by Specimen 10 from Spookys Jumpscare Mansion.