The main idea is that Styx is smaller than humans, so direct combat is never an option. Stealth takedowns, traps and such are the tools here. The enemies are delightfully stupid: sure, once you've been spotted they give you a chase and smack you about, but they also go back to their patrols if you manage to escape and hide for a bit. The usual "huh, must have been the wind" thing.

Gameplay can be a bit quicksave/quickload if that's how you want to play it. Levels are generally huge, but end up somewhat being obstacle courses with few routes which zigzag around the direct path through them.

The games are a bit "eurojank", sure, but imo, very enjoyable. But I am the kind of gamer who takes hours per level just so they can knock out EVERYBODY in the level, without raising alarms, just because that's fun to me, so I might be a bit biased. :P

All in all, since you already got them, give them a whirl? The first levels tell you pretty fast if you like the gameplay or not.