He has a good HP stat of 1401 and a great ATK stat of 1804. Although he is not the strongest character in the game it is his Ninjutsu and Secret techniques that place him in the top spot.
Ninjutsu
His Ninjutsu costs 5 Chakra so is a little expensive and also has a low damage multiplier of 1.5. This means that before taking into consideration modifiers he hits for 2706 damage but his Ninjutsu is AOE and its range is that of a mid range circle. The Ninjutsu has the added ability of a 70% chance to immobilize the enemy/enemies for 1 turn which is a good chance and can stall bosses for you.
Secret
His Secret technique changes from an AOE to a single hit with a big damage multiplier of 6.8 meaning he deals damage of 12268 before modifiers. As well as that incredible damage he has a 40% chance to seal the enemies Ninjutsu for 5 turns. With both the ability to immobilize and seal his enemies he is a must have character.
Range and Skill
He has a short attack range and also has a counter attack Field skill which is useful for a character with high ATK stats. His Buddy skill reduces damage from Body type characters by 20% so clever switching with tank characters can allow you to easily stall for your Secret techniques to finish enemies off with.
Pros
Very high stats
Can both seal and immobilize
Buddy Skill allows tanking Body hits easier"
Cons
Short ATK range
Thanks to bfw182 for his awesome evaluation notes!