1. Hashirama Senju: Second Hokage of Konoha, developed Multiple Shadow Clone Technique, Exploding Tags Multiplication, Soul Binding, and Reanimation.
2. Orochimaru: Obsessed with immortality and all ninjutsu. Created Cursed Seal, Impure World Reincarnation, and Eight Branches Technique. Eventually became a traitor but respected for his pursuit of knowledge.
3. Kabuto Yakushi: Orochimaru's follower, excelled in Impure World Reincarnation and the use of Hashirama's cells. Turned over a new leaf and became the director of Konoha's orphanage.
4. Akahoshi: Developed forbidden jutsu "Kimagurena-Paro" and almost became the strongest ninja. Defeated by Naruto.
5. Naruto Uzumaki: Inadvertently created powerful techniques, including Wind Release: Rasengan. Developed forbidden jutsu by testing on his own body.