Crimsonland is now available for Linux. The supported Linux distro is Ubuntu but the game may work on others too.
It took a bit longer than expected but we're finally here. We had the Linux version in beta for a while and after that we fixed a couple of bugs. The current version should be good, but we have limited number of Linux test machines so please give us feedback here: http://steamcommunity.com/app/262830/discussions/0/540744299873559238/
Have fun blasting some Linux-powered-zombie arse!