Name: Insanity.
Powers: 
Madness incarnate: He is able to manipulate the madness of others. He also can detect fear and pain easily, meaning that if he were to watch someone for a long portion of time, he would discover their fears and weaknesses.

Compulsive madness: Should he find someone he wishes to destroy, insanity will devote himself to the task, ignoring food and drink for long periods of time to allow him to stalk his target. This in combination with Madness incarnate makes insanity adapt at learning weakness about his foes.

Eternal suffering: No matter how insanity is killed, he will always revive if darkside still exists. However, this can be used as leverage against him, if someone can threaten darkside.

Insanity's mask: Should he need to corner someone while alone, with out scaring them off, insanity can mimic a friend, or family member's appearance. Or, in some cases, make himself look like the thing they fear the most.

Infestation: Rather than killing someone, insanity will enter into their mind and wreak havoc, most of the time turning them into a murderous nut case. In best senerio they manage to just remain in a corner curled up because they are seriously messed up.
 
Insanity also has a large amount of knives on his person, for if he ever gets corner and needs to cut his way out. He is extremely skilled with knives, but he lacks knowledge on how to kill, focusing more on maiming and harming.

Looks: [img=http://ludeon.com/blog/wp-content/uploads/2014/01/RandyWeb.jpg]

Theme song: Insanity by volcanoid.