Skeletorus

Skeletorus is one of the eight fallen heroes from Warcraft III Warchasers scenario map. His appearance is similar to the creature that was trying to protect Arthas from the cursed sword. His inability in this might have caused his downfall. His voice is Lich's

Chain Lightning

 * A chain that jumps from one enemy to other. Can jump max 8 times. Every jump reduces power of the lightning.

Mana B urn

 * Sends a bolt of negative energy that burns a target enemy unit's mana. Burned mana combusts, dealing damage to the target equal to the amount of mana burned.

Brilliance Aura

 * Gives additional mana regeneration to nearby friendly units.

Death and Decay

 * Appears to be some kind of spell that saturated the air with acidic chemicals that eats through armor, stone and flesh.