I play this game since 2014 and I always play it just for fun. I never spent any money on it because ninjas that today are awesome and practically invencible (Obito 10 tails Full BT, Madara Edo Full BT, Naruto Sage of Six Paths Full BT, etc...), they will be free or easy to get sooner or later. I remember when Naruto Ronin was the strongest ninja and everyone spent money to have him, or even before him when Kakuzu Earth Grudge Fear was one of the strongest. Right now, you have Pain Six Path Rinnegan, Jiraiya Rinshou, Orochimaru GNW, Asura, Indra and others that put Naruto Ronin on a corner! So, just play and have some fun.