You can never kill too many orcs. In fact, if Lord of the Rings is anything to go by, you can grow them, and they serve no purpose other than to look menacing and maim things.
Finally, as a result of the follow-up to Orcs Must Die, you’ll get to take those pesky beasts on with a coop partner. The game will also feature brand new levels and spells, in addition to a revamped upgrade system. Right now, it looks like we only have confirmation on a PC version of the game.
[Source: Orcs Must Die 2 Announcement trailer]