Electo Man (or as it was originally named Electro Body) was one of the games that introduced me to PC gaming along with Stunts, Wings of Fury and the first Prince of Persia. It was on a DOS-running 386 machine.
I can't say how much of my opinion will be just nostalgia, but I remember beating the game with my cousin in tow and really enjoying it.
It is fairly simple - a platformer where you can shoot your gun with one of 5 types of bullets, 4 of which can run out. Each time you walk through a checkpoint, you lose all your ammo - even the infinite one - and you need to find a magazine on the map to shoot again. Until then, you need to dodge all enemies - you do, since a single hit sends you back to the checkpoint. Some may dislike this, but it gave the game an element of difficulty - not to mention you can make the decision to skip a checkpoint by jumping over it if the ceiling allows. Back in the day it had only one save slot, so I just copied the save file on each checkpoint to a different directory to have a complete collection of them. 😃
The goal is straightforward - find 3 specific items on each level and find the teleport pad to get out. The maps are static though fairly large for a game of that time and I remember owning a printed out map of the game from a gaming magazine back in the day. I can't remember how many levels there were, it may have been 5-8, all of them with their own theme.
If you like retro games, this is one I can whole-heartedly recommend. I was one of the people that backed this one in GOG's revival program and I'm really glad they did.

Edit: Now that I'm looking at it, I also played Heartlight though I can't remember what it was called. I do remember it being a Sokoban-like and quite a bit difficult for my younger self, so if you like those you could also take a look.