It's been a long road for Battleblock Theater, spending years in development over at The Behemoth.  But today, it's finally out on Xbox Live Marketplace, and players can invest hours at a time running through booby-trapped mazes while an audience looks on, either alone or with a buddy through local and online co-op.

But The Behemoth, ever graceful to its fans, have offered up some additional rewards for long-time players of their games.  Those who own both Alien Hominid HD and Castle Crashers can unlock additional characters in Battleblock, including an alien and knight from their respective games.  Other characters can also be unlocked, depending on how many Achievements you earned in those prior games.  (This video explains it all.)

Want another bonus?  If you own Castle Crashers and unlock enough Achievements in Battleblock, you'll be able to play as Hatty Hattington in that multiplayer brawler.  Isn't that nice?

And if you didn't pick up Alien Hominid HD and Castle Crashers yet, relax, you can still get them pretty cheap on Xbox Live Marketplace, for 800 Microsoft points ($10) apiece.  They're well worth picking up…along with Battleblock, of course.