At your level? just keep it.Just work on having your first super rare ninja then make a lineup around that ninja, then get your second super rare then work on how to use them both then get your third and so on. With the way NO works now, your strength is highly depended on how many super rare ninjas you have, of course BP matters but unless o can out power your opponent by like 80-100k BP, then your ninjas would dictate your victory.