Richard the Rooster: No special ability. Brings Jacket's Piece and a Baseball Bat.
Rasmus the Owl: Can see the outlines of people, weapons, and items of interest through walls.
Don Juan the Horse: Doors become much more lethal.
Tony the Tiger: Killing punches, NO WEAPONS.
Aubrey the Pig: "Gun lover" Can always find a loaded gun when needed. Brings a double barrel shotgun.
Dennis the Wolf: Brings a knife and somehow always has another knife even after losing the first one.
Brandon the Panther: "Gotta go fast" Walks/Runs faster.
Carl the Grasshopper: Brings a drill and hammer.
Earl the Walrus: Higher resistances to almost all forms of attacks (bullets, melee attacks, holy/unholy attacks, etc...)
Peter the Unicorn: Total silence. Brings a silenced Beretta.
Richter the Rat: Brings a silenced version of Jacket's Piece
Alex/Ash the Swan: Chainsaw and Guns
Jake the Snake: Killing throws.
Willem the Monkey: Rip and steal the enemy's weapon out of their hands while killing them in the process.
Rick the Fox: Marksman. Brings a .308 sniper rifle.
Mark the Bear: Brings dual MP5s and medium body armor.
Jones the Alligator: More gore and brutality to each kill. When doing a execution, it could inflict panic amongst any nearby enemies.
Ted the Dog: Hostile dogs won't attack but instead they could be befriended to fight for you, as long as you have the mask on.
Louie the Chameleon: Harder to spot to point where you could probably stand in front of a guy and he doesn't even notice you.
Rami the Camel: More ammo for every firearm. Each kill returns a bullet to the gun.