Just clever use of tiles, proper encoding of assets, and making you code lean. Back in the '00s, I made a j2me mobile realtime multiplayer online strategy game

Just clever use of tiles, proper encoding of assets, and making you code lean. Back in the '00s, I made a j2me mobile realtime multiplayer online strategy game, which included animations, music and sfx. It was 60kb, because I wanted to target as many devices as possible. Later it grew till about 200kb Lots of space and performance optimizations.