Conversation so far:
What other versions of M. Bison are there?
In Street Fighter EX2 Plus for the arcade and PlayStation, another version of M. Bison appears called Bison II as a secret final opponent in single-player mode.
What other versions of M. Bison do they have in the games?
In Street Fighter EX3, M. Bison II returns as a playable secret character.
Does M. Bison have other names?
Shin-Bison
Were there even more versions of M. Bison?
Shadaloo-ISM

Question: What was different between the characters?
Self-contained rewrite: What was different between the M. Bison characters?