As for me, there was a time wen i was a huge fighting aficionado, digesting them left and right, and even though i slowed down quite a couple of notches over time, still have a number of favorites that i go to, there is one that i haven't put down.
The Guilty Gear XX series and all of its versions
Specifically Guilty Gear X2 Reload, that's the one i played religiously years ago, that's the one i'm always going to wen i need my fix, and that's the one i replay at least once a month (there's a huge SP story mode). Amazing music like this aswell. Overall, i love this game so much.