Bug: Amulet of Sorcery (I think that's what it is) gives -130% Mana Usage, basically free Hypnotise, Blizzard, Fireball etc. =)
Not sure if it's been reported, but whenever the unit with Amulet of Sorcery would have spent mana, they don't pay any, including Sov spells. You can get some pretty cool armies of SK troops once you can cast multiple spells in a battle. ![]()