Id say Naruto.
As the title says, "World" not Story, If you took out the key characters, youd have a solid MMORPG.
Character Development would be darn cool, you could go Taijitsu, Genjitsu or Ninjitsu or a mix of everything, could have all the Jitsus from the Animé and more, therd be hundreds of possible Classes though Itd be good if Character Customisation was left open ended (No Set Class, but Reqs for casting skills). not sure about Clan Bloodline-Limits though, theyd have to original (or from Animé) and contain downsides (Sharingan causes huge Chakra Loss, byakgan causes loss, but not so much)
PvP would be VvVvV (Village Vs Village Vs Village) or whatnot and the game would be largely mission based (isntance maybe?) and ranks could be determined by Your Level (Genin,Chunin,Jounin) and unlock harder missions (as seen in Animé)
I dunno probably sounds sad, but the Naruo World would be a great mmorpg if done right.



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