We need to talk about the monkey (HEAVY SPOILERS) WHAT?!

I emerge battered but victorious after cutting the fuckers head off. Get the shinobi execution screen, go to leave the arena and then... and then...

HE COMES AT ME HEADLESS?! And where did he get the sword?! 

Wtf. So cool. How the hell am I going to get past this one though. Phase 1 is brutal enough. 