Yea can anyone tell me how in the hell u r suposed 2 beat duke

Depends on the character. I know a couple of strategies.

Any Character:
Jump attack follow into a combo, back off and Jump attack. Repeat.
This is not easy but it works

Rock:
Run and get close and do his throw move followed by the blast at the end. Note- This move will disrupt even Ground Collapse.

Experience is the best teacher so instead of asking others how to beat someone practice against him often until you learn to beat him.

Duke is easy. want a challenge try him on he hardest difficulty, then talk about how to beat him. *lol*

Like him, you keep him trapped in the corner.

Beat the game with the two brothers, Alba and Soiree and u unlock him.

Hm.... Another way of defeating him is by using fast attacks. There are many ways actually. Just watch out for his ground collapse, he tends to use it a lot.

You just have to watch out for that one move he does that burns the ground. You can block that. Otherwise use combos on him and he's pretty easy.

Easy or not he tends to get really annoying.