My demonstration for Battleblock Theater was not one of these magical instances -- not due to the nature of my unacquainted co-op partner, but because of the many, many ways The Behemoth's latest allows you to royally screw your accomplice. With so many annoyances at his disposal, I can't really blame him for his malfeasance.
Players have access to the same suite of platform-navigating abilities afforded them in the game's competitive modes, including basic melee attacks and one special power, which they designate before kicking off the game. However, there's more of an emphasis on helping your partner achieve common goals to solve puzzles in order to collect as many gems as possible. These maneuvers include throwing your friend across a dangerous chasm or hoisting them up and over a ledge -- all of which are done with one context-sensitive button.
Of course, the shine comes off the apple when you realize that your friend is actually a straight-up bastard, who'd rather hurtle you into a nearby wall of retractable spikes than fling you into a nearby button. Fortunately, the beauty of the demo I played was this: When the co-op elements worked, the end result was pretty satisfying, and when I was (frequently) betrayed, the end result was still pretty satisfying.
I thought I'd seen the extent of man's inhumanity against man in my previous, competitive hands-on experiences with Battleblock Theater, but as it turns out, the betrayal of a co-op partner leaves a much deeper sting. Perhaps my deaths were accidental -- but judging by the smirks I caught in the reflection of the demo unit's screen, I expect this was not the case.
Still, though I spent most of my time during my demo getting murdered by my new colleague or getting my revenge, my raw enjoyment convinced me that I wasn't exactly playing it wrong.