All the above mentioned.
And you would have to study him and learn how to counter his counters so he can be caught and feet end in the right place at the right time. Straight fighting isnt going to help much as Boom said he leans or rolls with whatever he sees coming anyway. Leg flexability, core strength cardios, skipping in squats and raising up with uppercuts, continential cup a piss, you name it, you'll need it.