It still has some bugs, but I think that the basics of the MMO engine work. MMO stands for Massive Multiplayer Online, and in theory, it should be able to deal with infinite online players, but scratch has the 256 character limit on cloud variables, so there is a player limit. How it works, is instead of having the players using the same variables for every frame, it makes the player use the variable once in each 5 frames, or more, if there are more than 10 players. Instead of loading the data from that frame only, it loads the data from all the frames since it was last updated.
