2.0-alpha12 is a really small fix: playing Kiki online often crashed the game. This is no more the case.

What happened?

When the game receives a message from the server, it deserialize general information such as the damage for each character, then ask character-specific code to deserializes data unique to them. For example Kiki has code to correctly update her platform when the game rollbacks.

Kiki's code did that properly, then instead of telling that it just read 15 bytes, it announced to have read -86 bytes. Yes, this is nonsense. Subsequent reads, by the other character or the stage were corrupted. As the NES provides zero protection against such invalid reads, and Super Tilt Bro.'s code favors going fast over continuously checking what it reads, it resulted in random effects, like corrupted sprites or crashes.