Bushido Blade

If your legs are taken out and you can no longer stand up,you can forfeit by pressing select, he will mumble some words and your opponent will kill you.

To play with the Executioner, complete the Slash mode with the gun guy. Choose the HARD skill, and no continues. That means, you must kill 100 men with one life.

Go to story mode. press L1, L2, R1, R2, START, and SELECT simultaniously. You will now be able to run from arena to arena.

To play as the gun assassin,

Complete the Chambara mode, in other words, kill 100 men in the Chambara mode without your character getting killed even once. Which means no cotinues. Getting injured is OK. After you kill 100 men, you will have obtained a contract with the gun assassin. Now the gun assassin is playable.