Just by the nature of the viewpoint, FPS games achieve a level of immersion other genres can't really touch, and under certain circumstances, that can lead to some quite unique gaming experiences. I'll preface by saying that I've mostly only played good FPS games and I'm not overly acquainted with some of the incredibly insane older stuff like this and all the gonzo WOLFENSTEIN clones on the Pie in the Sky engine and whatever else, so I'm sure that there's probably quite a few games that would elicit this response from me - but I found PO'ED to be a uniquely hellish and disorienting experience that I needed to put down pretty much immediately because it felt like playing an actual nightmare. (Like, I was okay, I wasn't having a panic attack or anything, it was more like my brain was just kind of gently rejecting the inputs it was getting, like there was a small red warning light blinking on the dashboard of my mind saying, "hey, you should really turn this off" with increasing urgency the longer I played.)

You skate around these stark abstractions of spaceship interiors, hopping across single-flat-polygon platforms and elevators, level geometry seemingly assembled at random, wildly swinging a fucking bloody meat cleaver at these horrors, these puzzlingly formless and yet somehow sexualized enemy sprites, and trying desperately to keep your senses as the PS1 wall textures swimmmmmmm and tillllllllt. Judging by the manual, I guess the tone is supposed to be ... funny? Like tongue-in-cheek? But I mostly just felt like I was experiencing some talentless, deranged game designer's version of Vincent D'Onofrio's mind palace from The Cell.

Extraordinarily bad vibes. Not recommended.