When Reborn attempted to teach Zettai Maken to the trio, they went through hard training that increased both their physical condition and their spirit. After they were done, Reborn showed them what it was about and used it on Yamamoto, Ryohei and Gokudera. All three of them admitted defeat before they could do anything. When Tsuna first tried it, he failed because he wasn't 100% sure about himself. Kyoko and Haru never really used the technique; however, the training taught them how to control their spirit.
- "Zettai Maken" can mean either "absolute evil fist" or "won't lose."
- According to Fuuta, it is ranked third in martial arts that should be sealed away in the 4000 year history of China.
- The auora of the Zattai maken look like the mixture of storm and cloud of gokudera's sistema C.A.I