The Mysterious Beast: In the ninja world, there are intelligent creatures that predate humans. Toad Mountain's Gamamaru warns the two sons of Kaguya Otsutsuki that her control and energy absorption from the Divine Tree will drain Earth's resources. They saved the world, allowing humans to rise. 

Spiritual Beasts and Ninjas: Ninjas and spiritual beasts have a partnership. Spiritual beasts can be summoned by ninjas to assist in missions.

The strongest is Enma, the Third Hokage's summon. Enma's power surpasses the legendary Sannin's. Enma can fight, use ninjutsu, has a diamond-hard body, and transforms into a staff. 

The Fear-inducing Duo: Enma's ability to transform into a staff provides an efficient surprise attack. Orochimaru was overwhelmed by Enma's strikes in their battle. However, the Third Hokage died, and Enma disappeared.

Even though revived, Enma was never summoned again. Konohamaru, the Third Hokage's grandson, didn't inherit the bond.

The Disappearance of Enma: It's intriguing why the Third Hokage forgot about his summoning contract with Enma. The once-revered spiritual beast seems to have vanished without a trace.