I wrote about it briefly back in November last year, but back then it had no solid release date. That's changed today with the official announcement along with this new trailer:
It sounds like it's going to be pretty decent, since it's not your standard beat 'em up. You will study enemies, parry, dodge and essentially let enemies defeat themselves by draining their stamina. There will be a levelling and upgrade system, fully remappable controls, a story mode and even an arcade mode.
To be sure about the status of the Linux version, I spoke to the developer on Twitter today who confirmed that Linux version will be available at release. Great news, as it looks like a damn fun game.