I was thinking how to bring Itachi back to the game...
Here is my idea of SB. It would be amazing if he was another 3* Skill trial ninja such as Hashirama, since he is very expensive in events, fairly outdated and hard to get...
(godly wish, but whatever..) here is the idea:

Mystery +2: Causes undodgable Ninjustu damage to the selected opponent´s unit and chaos for 2 rounds. Suppresses immunity to chases for 2 rounds. After using it for 2 rounds, it will start to cooldown for 4 rounds.
Mystery Y+1: Causes undodgable Ninjutsu damage to the selected opponent´s unit, chaos for 2 rounds and increases target´s mystery cooldown by 1 round. After using it for 2 rounds, it will start to cooldown for 4 rounds.

Standard +2: Attacks all the opponents´ units in the front column and has a guaranteed chances of causing repulse. Decreases opponent´s defense and resistance by 10%. If killed by this attack unit cannot be resurrected. This skill is unavoidable.
Standard Y+1: Attacks all the opponents´ units in the front column and has a guaranteed chances of causing repulse. Decreases opponent´s attack and ninjutsu by 5%. If killed by this attack unit cannot be resurrected. This skill is unavoidable.

1st Chase +2: Chases a repulsed enemy, causes low float, critical hit and dispell any buffs and shields on target.
1st Chase Y+1: Chases a repulsed enemy, causes low float, critical hit, suppress immunity to debuffs and causes chaos.

2nd Chase +2: Chases and attacks high floated enemy, causes low float, 10 combo and undispellable ignition for 3 rounds.
2nd Chase Y+1: Chases and attacks high floated enemy, causes low float, 10 combo and enfeeble, ignition for 2 rounds.

Passive +2: Itachi is immune to chases and debuffs. For every chakra over 20, his ninjutsu, resistance and defense is increased by 2%.
Passive Y+1: Itachi is immune to chases and debuffs. When hit by Ninjutsu dmg, has a 45% chance to cause Fear and absorb 40 chakra.