Since its not really a spoiler anymore as so much has changed that the Web Comic is just a very rough outline, in the Web Series, King basically didn't do anything in the final fight, and Atomic Samurai pretty much confronts him, gives him his sword, and asks him to cut an apple for him. Atomic Samurai has a speech/inner monologue about no matter how he cuts it, he can see everything he needs too about a man based on how he cuts the apple. King sits there with the sword in absolute terror realizing he has no way out of this situations and doesn't know what to do, before eventually giving up believing he's been caught, placing the sword down, and walking away having done nothing.
Atomic Samurai just assumes Kings actions were so fast and beyond him he didn't even realize King had already swung the blade, and the Apple didn't even know it had been cut yet.