Skeletons which spawn in the Nether are now Wither Skeletons, which fire Wither arrows!
(Configurable) Allow wither skeleton archers to spawn with armor and enchanted items!
Configurable spawn density; by default on normal, only half of skeletons will be replaced, and on hard, all skeletons will be replaced.
Wither Skeletons can shoot Wither Tipped Arrows, and can also be configured to drop them!