1. Scorpion's Fourth Scroll: Scorpion's trump card remains a secret within the contents of his fourth puppet scroll. 

2. Shikotsumyaku: The specifics of the Shikotsumyaku Sage Mode, obtained by the Kaguya clan, are unknown. 

3. Chakra-Countering Jutsu: Hashirama taught Sasuke a chakra-binding jutsu as a countermeasure against Madara, but its details remain undisclosed. 

4. Susano'o without Sharingan: Uchiha Madara's ability to activate Susano'o without his eyes raises questions about its intentional design or creator's mistake. 

5. Minato's Death: The cause of Minato Namikaze's death remains a mystery, as there is no evidence of him being killed or having a terminal illness.