All the textures were in the game's palette. I then tried to get all the ingame colors use it with glsl, but that was just so slow. With some crazy if/else jungle I was able to get some 80 colors without too much performance loss. In my other project I also tried some light boost/diminishing with a dynamic light, and sort of multiplying all colors with glsl, so it gets kinda dark, but that didn't work exactly as I wanted.
The main reason for the change was to have lots more monsters on screen and actively chasing/attacking player.
1600 monsters in the level, all active at the same time. This is totally possible now, except impossible to survive it without cheats. But if I figure out someway for player to survive, I'll have that kind of thing somewhere: