Feral Interactive released HITMAN: The Complete First Season today for Linux just as planned. HITMAN for Linux can work with the Radeon drivers and Feral recommends at least a GeForce GTX 680 or AMD R9 270X as a minimum while the recommended GPUs are the GTX 970 or R9 290. If using Mesa, it should work with Mesa 13.0+.
HITMAN for Linux can be bought from Feral's store or the Steam Store for 50% off. I'll have many GPU/Linux benchmarks shortly, assuming the benchmark mode meets our criteria.