Instructions
Move to the left of the screen and use McTwisp's roll to dodge around Stayne's attacks. Try to get behind the boss as soon as possible.
Attack Stayne once you are behind him. Hit him as much as possible until he goes into his spinning attack. Roll out of the way when this happens.
Continue to roll around dodging Stayne's attacks until Stayne rolls a large spiked ball at you.
Activate McTwisp's "Time Reverse" power when the ball starts rolling at you. This will reverse the ball's direction and send it straight back at Stayne to cause massive damage.
Repeat steps 1 through 4 until Stayne finally collapses.