Many games try to blend tower defense and shooter combat. Orcs Must Die succeeds in a way that many others do not. It manages to make tower type and placement, and your ability to land headshots and manage special abilities feel important, powerful, and necessary to your success or failure. It’s a game that understands tension curves; there will be waves that are sure things and waves that you swear you wouldn’t have survived if you’d been prioritizing targets with your special abilities.