As of 0.318 a single type (human fighter) is created.
A work around is create the type of Hero you want, save, restart Game in Debug/god mode and import saved game. Does not garentee they will be immortal.
Hmmm... we probably want to go through normal hero creation in debug mode from now on. Will be better for testing purposes.
We should keep the "ESC" shortcut to debug mode though. You'd be amazed how much time that saves me in an average development session....
OK Religated to the undocumented cheat sheet. But when your hero is killed for the umteenth time. ;)