Few skills:
-- Elementalus Ultimatus -- (sounds lame, eh?)
Type: passive.
Effect: There is a chance of casting one-hit-kill spell of 1 of the 6 elements.
Darkness: Simply pulls the enemy to the void.
Light: Smite, for the defilers of the land! (just something that looks like a smite

)
Earth: A boulder falls from the sky on a unit.
Nature: A unit turns to a treant, turning against the old ones.
Fire: a unit gets crushed by a fiery meteor (also leaves afterburn for awhile).
Water: OMG FLOOD! (a unit gets flushed away).
-- Elemental Masteries --
Type: Passive (again).
Effect: Same as before, but different effects.
Darkness: A unit dies instantly and turns to a skeleton, fighting for yer side.
Light: A unit sacrifices himself for god.
Earth: The earth devours the unit.
Nature: null (couldnt think of any).
Fire: A unit starts to burn, dealing alot of damage per second. After it dies, it leaves an afterburn.
Water: A unit gets sea sick and pukes, taking damage.
-- Armageddon --
Type: manual casting.
Effect: First, the units in the area (AoE) gets damaged by shadows for low dark damage, then after the shadows disapear, they get smited by light, losing average health based on light damage. After the smite, there comes an earthquake, damaging the units who goes through it with earth attack, then it turns to poisonous area, doing nature dmg over time, and after that there comes an meteorite, damaging everyone with huge fire damage. And finally, a huge tidal wave comes and does enormous water damage.