Thanks to bfw182 for his awesome evaluation notes!
Kabuto Yakushi (The Sound's Spy)
Kabuto is currently the most important support character in the game. He is recommended for nearly all occasions.
The reason why he is so good is that his Ninjutsu is currently the best healing one in the game. He heals you by 1780HP and at only a cost of 3 Chakra means he can be used numerous times throughout the battle.
His field skill is also a healing ability so when you use his Ninjutsu to heal someone you actually nearly recover 2000HP.
His typing is Wisdom meaning that he also isn't weak against any other enemies.