Vileblood (3.5e Template)
From D&D Wiki
Creating a Vileblood
Size and Type: The creature’s type changes to monstrous humanoid. Do not recalculate base attack bonus, saves, or skill points. Size is unchanged.
Hit Dice: Increase all current and future Hit Dice to d12s
Speed: Same as the base creature.
Armor Class: The flesh of vileblood creatures becomes tougher and more resilient. Add +4 to the natural armor bonus of the base creature if it is Large or smaller, if it is Huge or larger, add +8.
Attack: A vileblood retains all the attacks of the base creature and also gains a bite attack if it didn’t already have one. If the base creature can use weapons, the vileblood retains this ability. A creature with natural weapons retains those natural weapons. A vileblood fighting without weapons uses either its bite attack or its primary natural weapon (if it has any). A vileblood armed with a weapon uses its bite or a weapon, as it desires.
Full Attack: A vileblood fighting without weapons uses either its bite attack (see above) or its natural weapons (if it has any). If armed with a weapon, it usually uses the weapon as its primary attack along with a slam or other natural weapon as a natural secondary attack.
Damage: The vileblood creature's claws lengthen, teeth multiply, and muscles harden. The damage die used when the creature deals damage with natural attacks increases by one die type, so that 1d6 becomes 1d8, 1d8 becomes 2d6, and so on, as if the creature were one size larger.