IGN has first details on Orcs Must Die! Unchained, a new OMD-based MOBA from Robot Entertainment, saying this will make its free-to-play launch later this year. They have first details on this "5v5 multiplayer game (with solo and co-op vs bots!) for the PC that fuses the OMD! action, strategy, and style with elements of both MOBAs and customizable card games." The game is on display at PAX East and a reveal trailer. Here's a bit:

“We’ve been calling it a fortress siege game,” Robot CEO Patrick Hudson says, explaining the simultaneous attack-and-defend flow. Picture it: instead of just defending against waves of enemies with a maze of gleefully sadistic traps, you get to do that and lead waves of AI allies into head-on battle in an effort to push through someone else’s sadistic traps to reach the other team’s fortress.

By the time of its anticipated launch in late 2014, Robot plans to offer dozens of playable hero characters on two factions: humans of the Order (which has been rebuilt by the War Mage and the Sorceress after OMD2) and the new monster heroes known as the Unchained, who’ve emerged from newly discovered rifts. Each hero is designed with a role in mind, such as offensive melee-focused characters, “leaders” that buff minions, support characters that buff other heroes, defensive classes that can improve traps, and more. Most characters will have at least some ability to sabotage enemy traps to help their minions.