This is a Guide for the "Perfect K.O" Mission.
I had alot of trouble defeating Ryu while he has full health, and he kills/K.O's you in only 1 hit, so I made this Guide for anyone that has trouble with it.
When the fight begins, press RB so you roll towards him (Note, he may attack you with the spinning kick attack, if timed correctly he shouldn't hit you), once you are out of the roll spam B. Keep spamming B until he falls/flies to the ground. Once that happens, press RB twice, so you're right next to him and execute a Y attack. Doing so will take 1/3 of his health. Then you have to back off. (Don't stay close to him, so he can't hit you) His own Burst meter should be quite high, and he can execute you while getting hit, very annoying. So now that he is standing, press A and X. Keep spamming the A and X combo and he should either get hit by the fist, or jump and still get hit. Keep repeating until his health is completely gone and you win the Match.