This is mid 90s, I remember playing it on a PC that didn’t even have Windows on it. It was an alien invasion side scroller. You’re some action dude that has to fight his way through the levels, some of the early enemies are little blobs that jump at you.
Any help appreciated :)
Edit: found it, it was Bio Menace! Thanks anyway for all the suggestions, folks :) Happy gaming!
That’s very little information and fits a lot of games. The two main ones that come to mind are probably Duke Nukem and Commander Keen. If it’s neither you can scroll through this list https://www.abandonwaredos.com/abandonware-list.php?tp=1&kword=202 it’s not complete but maybe you get lucky and recognize it.
EDIT: Somehow said Doom when I meant Duke Nukem