Imagine Diablo, but where your mate plays the devil. That's essentially the pitch for Breach, an asymmetric dungeoneering romp from some of the devs who worked on Star Wars: The Old Republic. Fifteen-minute matches pit four players against a "Veil Demon", a fifth human who controls the dungeon and sometimes the minions themselves. It's out on Steam Early Access in January, and features the most nonplussed laser-firing bird creature I've ever seen.
If I'm reading that trailer right, the premise revolves around a rich dude who unleashes mythical beasties through an interdimensional portal in order to teach humanity a lesson about something. Humanity learns that lesson by hitting demons with swords, shooting them with guns, and zapping them with good ol' fashioned magic. I do enjoy seeing magical nonsense get tangled up with sci-fi nonsense.
There's an emphasis on character customisation, selecting different abilities to wallop bads in the manner of your choosing. You can swap character mid-game, too, a dynamic that immediately reminds me of hero switching in Overwatch. I fully expect to be shouted at for not playing the bored-looking owl. Or possibly FOR playing it, depending on how the meta shakes out. There's bound to be shouting, at any rate.
If they're doing their job right, some of that shouting should be directed at the Void Demon. It's a system that fellow dungeon 'em up Crawl has sort of dabbled with, only in reverse. That's a 1v3 local multiplayer game, where one hero chops their way through rooms while being mobbed by player-controlled dungeon fodder. I've only played it once, but I had a blast.
If you want to know more about Breach, cheery RPS fanzine PC Gamer got their mitts on it back in August.
Here's the Steam page, in case you wanna wishlist it. You'll have to pay if you want in at the start, though at some point down the line Breach will go free to play.