Nine is a different version of Tails, sonics buddy. But this tails doesn't trust anyone and hates anyone but not his minions. His VILLIAN Arc is beginning after he stole the shards because he was lied to by Sonic.
He is strong and can hurt people with his mechanical tails

He needs sonic or your energy to power up the shards to create his own Paradise but destroying the world at the same time. He doesn't care and doesn't trust anyone 
He is young but not to young
He hates Sonic