DLC trailer will be based on the Lord of the Rings scene "Ents attack Isengard".
Skaven will be destroying forest to boost the Throt's experiments. There will be underground facilities. Ariel will come with army of trees and elves and destroy the facilities (of course will include huge amounts of water
DLC pack => Ariel vs Throt (100% sure here)
Wood elf new lord type => Spellweavers High and Dark Magic (100% sure here)
Wood elf new hero type=>Shadowdancers (95% sure here)
new unit types => I have feeling that CA will give us Unicorn herd
and wood elf chariots plus additional 1-2 units
Drycha => FLC lord (100% sure here)
She will get approx. 6 reskinned tree units also heroes spellsingers will get additional lores of magic
New lord => Master Mutator (100% sure here)
New hero =>Packmasters /additional FLC hero => Chieftain
(95% sure here)
Throt will be able to create new rat ogre variations but we will only see different buffs. Probably only new model for rat ogre which we be able to see will be armored rat ogres.
Other new units: wolf rats (100% sure here) and probably (95% sure here) this big mama