Hey! PICO-8 is a game engine that tries to feel like a retro "fantasy console" by putting limitations on the screen, graphics, memory and sounds of the games you make with it. It's very simple to learn and very fun to work with and has an amazing community. It's paid, but if you enjoy making small games and the challenge of designing games with such limitations, you might want to try it out. Personally, it's among the best purchases I ever made and I love it. Hope that clears everything! :)