He repeatedly demonstrates that he's a better ninja than his captors (with the exception of their female leader, who always recaptures him)...despite not actually being a ninja.
Genchu and Hirotomo's duel is nothing but pure, distilled awesome. From the skill of the two combatants, their moves and countermoves, Genchu's unstoppable Roaring Rampage of Revenge, Hirotomo catching Genchu's blade in his hand after Genchu cut through Hirotomo's sword, and finally Genchu's massive headbutt to bring the fight to an end.
Yori and Ryoku's fights include moments such as:
A weaponless Yori disarming Ryoku by catching Ryoku's sword in an empty sheath, then turning around to use it against Ryoku.
Ryoku effortlessly blocking Yori's attack and getting his sword back.