adrenaline. I’m pretty weak on nerves, so a single close engagement is enough to get me on a high. for me its not a game i sit down and play for hours, mostly because after a few games(or just one) ill need to stop since i can’t use my hands anymore
also, its free.
and shotguns are king if you use them right. nothing beats that clustered “clang” hitconf. sounds of a shotgun headshot.