Kengo: Legacy of the Blade

To play in the Dojo Stage select versus mode than hold select when selecting a random option at the stage selection screen. To play in alternate versions of stages select versus mode than hold select when choosing a stage at the selection screen. Note: Only some stages have alternate versions.

First complete the game by killing all samurai masters
(kill them by learning all their moves, then fight them with sword)
normally after you've won the shogun tournament,
you'll fight Musashi who has a wooden oar.
After killing all samurai masters, Musashi will have 2 swords instead of an oar.
Defeat him, then in Versus mode select Musashi, hold select + X
and fight as Musashi with 2 swords.