What have you got? Wind boost combo (Gaara/Kankuro/Bakhi) is good in arena as the higher hp means it is easier to * around without the healing, provided you snipe their main damage ninja/combo maker asap (most of the time this is the main, but there are exceptions)

Empress is an easy combo to play (Hinata/Kurenai/Karin-or-Sakura) if your init is good. But it's a bit common so a lot of people will know how to counter it.