At the beginning these monsters are just a pile of bones. But when they stand up they form a skeleton monster that is capable of running fairly quickly. Their main attack is biting the player, and while it doesn't do much damage with every bite they can steal souls from player and healing themselves. And when they are about to die, they throw their heads at the player and detonating their bodies. They almost always appear in large packs.
This version resemble undead human with tied hands to their backs. They have the same attacks as normal bones but they don't steal souls and won't kill themselves when they are about to die.