What exactly do you want to play? Are we talking about single-player games? If so, then just find whatever you literally like. Use Dolby Atmos or DTS, or whatever you prefer. No one can give you perfect advice here; it all depends on your preferences.
Speaking of competitive FPS gaming (this is the only one that matters for this discussion), I'm a guy who spent a couple of years searching for the best headphone/DAC/amp combination. And hear me out, that high-end DAC/amp hype train is overrated. Nothing gave me better precise in-game positioning like the DT990/770 with Schiit HEL or a stock motherboard sound card like the 9018ESS.
I have about 10 pairs of headphones right now, including the HD800S, and they're good, of course, but I don't think they're the best for competitive FPS gaming. A lot depends on the DAC/amp you use as well. I have products from Burson, Schiit, and FiiO (K9), and I've owned many more before that I've sold. All you need is a neutral sound signature (almost analytical). Avoid anything warm or colored.