Unlock Ranaru and Nobunga
Start a one-player game. On the player one side,
put the cursor on the fighter Kamui and press Left,
Down, Left, Up, Left, Down-Left, Up, Right, Down,
Right, Up, C+D. The bosses should appear.

Time Attack
At the team select screen, set the cursor on Mezu.
Move left, up, right, you'll be on Gozu. Circle the
screen once counterclockwise, returning to Gozu.
Press D, you'll hear Jyazu's laugh. Jyazu is above
Gozu's panel, tap up to access him. (up again to
return to Gozu) It's the same for Shin Shishioh,
who is above Kage Shishioh's panel.