i beated like 4 hokkages an d still didnt went hokkage level..not that i really care about this achievement . dont wanna spent hours in vs fights for this hehe...
if you like it its cool though ^^.
@ some people: there is a ninja card in the corner of a waterfall aswell which is pretty hard to walk by or not find it.It was in the enemy camp and then there is a waterfall which you can go in the corner by some rockjumping.
Hope it helps for some ^^