I completely forget the name to this game but I've found it by chance on the net more than once in the past so I know it's not rare or anything.

Basically, it's a DOS game where you need to train armies in Medieval times and lead them into battle as one of the characters in said army. You could recruit a whole bunch of different classes and I think you could switch to them at will during battle. There was a multiplayer mode where at least two players could play cooperatively, playing as characters in the same army, and I also remember the game being extremely difficult, especially given how slowly everyone levelled up.

Character sprites were limited to tile sizes and I believe it ran in 320x200 256-colours, but I'm not 100% certain on that point.

I'm also still looking for that old Windows 3.1 dungeon crawl with solid red walls and a black background. No luck on that front. (Still not entirely convinced the game was ever released as I may've inadvertently been playing some programmer's own creation, given that I played it at someone else's place as a kid.)