Earth or Wind, problem with earth is mostly what Qv is saying but the buffs he gives to the team are just dammm, you can kinda counter that with having good init on samui to stop lightning main (with that skill he is not usually first position), with masked man there is nothing to do, but thats just why masked man is one of the best ninjas out there. Wind for the skill refreshing, Ay skill countdown is way 2 much in some battles but i still suggest earth, i was able to jump to six path rank on arena and not even with darui, i did it with omoi.

the issue of omoi is that you have no control on who he will target with his standard attacks, and if ay and samui didn't start a combo it's a real issue, overall if he targets some ninjas like roshi or 6 tails.