There were some games in this jam that used the concept of playing two characters at the same time. But his game stands out from the others, because the four characters have a fundamentally different moveset. This creates a lot of depth in solving puzzles.
Personally, i feel like the levels with the star to be the most difficult of all and was happy when i made such a level. Getting into diagonal moveset while i still have to watch out for the other characters is really difficult.
Overall i think this is a cute little puzzle game, with lot of depth. Great work.