Seen a trend with these relaxing games online and was curious what the complete opposite would be.
I was going to say that as well, its mostly timing not fast reflexes. I can see why people would think the games are stressful but that isnt whats good about them IMO.I'd argue that Dark Souls can be kind of chill in a way.
Doom or one of those intense/complex simulators like Civ 6 or Hearts of Iron, I'd think.