I looked through the code hoping to find any more special abilities, but didn't see any.
All the code for handling input, including special abilities, is in
RogueCastle.PlayerObj.InputControls(). It's rather large, but the part that controls the special abilities is short and straightforward. Pressing 'block' while holding 'down' as the Paladin calls
RogueCastle.PlayerObj.ActivateTanooki() (or, if you're already a tanooki,
RogueCastle.PlayerObj.DeactivateTanooki()); however, there is nothing unexpected for any of the other classes.
I looked through the rest of
InputControls() to see if I could find anything out of the ordinary, but everything was normal. That of course doesn't mean there aren't any other secrets in the game, but it's a pretty strong indication that there are no other secret special abilities.
As a bonus, here are all the possible states the player can be in:
public const int STATE_IDLE = 0;
public const int STATE_WALKING = 1;
public const int STATE_JUMPING = 2;
public const int STATE_HURT = 3;
public const int STATE_DASHING = 4;
public const int STATE_LEVELUP = 5;
public const int STATE_BLOCKING = 6;
public const int STATE_FLYING = 7;
public const int STATE_TANOOKI = 8;
public const int STATE_DRAGON = 9;