Boss rush mayhem:
Titan Souls (PC)
This boss rush Soulslike comes with an interesting twist: You and the boss both die in one hit, but you've got only one arrow and the boss can be damaged only when you shoot their weak point. Also, your only other ability besides shooting is to roll, so to succeed, you'll need to learn the patterns of each boss and avoid their attacks and then hit their weak spot when it's exposed.$15 at GOG
If we had to choose
All of these Soulslikes are excellent games, and I recommend checking them all out if you have the time and patience to overcome each one. However, if I had to recommend just one, it would be Nioh 2: The Complete Edition. It's easily the most fluid and engaging Soulslike I've ever played, and the wealth of content it offers means that you'll get a lot of bang for your buck.