Indeed Orcs Must Die!, and they must continue to die, as developer Robot Entertainment has released a new downloadable content pack with new levels, enemies, and more. It's available now on Steam with a special launch discount.
The 'Lost Adventures' DLC adds five new levels, two new enemies--the Frost Bat and Cyclops Mage--to fight on them, and the energy-recharging Mana Well trap to help you fight them. You'll get to collect even more skulls for upgrading your arsenal.
Lost Adventures will typically cost $3.99, but a nifty launch discount briefly brings it down to $2.99. Head on over to Steam to buy it. There's no word on it'll be released for the Xbox Live Arcade edition, but the first DLC has still yet to make it over.
Robot has also enabled basic mods by releasing tools to create your own custom enemy waves.
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