Databook 3 - Doton: Domu:
Earth Release: Earth Spear* (土遁・土矛, Doton: Domu)
Ninjutsu, B-rank, Supplementary
User: Kakuzu

A body like diamond, repelling everything!!

With the chakra flowing through all parts of one's body, the skin is hardened, increasing its defence power to its utmost limits. Furthermore, the destructive power of human bullet attacks** is increased, making this a great all-purpose technique. The amount of techniques that can break through the areas hardened by the "Earth Spear" are close to zero, not including its undeniable weak point: "Lightning Release Ninjutsu".

[picture of Kakuzu's arm turning dark]
←With one hit of Kakuzu's hardened fist, the gates of the Temple of Fire are destroyed.

[picture of Kakuzu's face being cut by Raidou's sword]
↑By invoking this technique the instant an attack hits, one gains an immortal body.

*The names of Kakuzu's techniques don't make much sense at first sight. This is because Kishimoto took the names from the legendary mecha anime "Mobile Suit Gundam" (機動戦士ガンダム, Kidou Senshi Gandamu), slightly altered them in some cases, and thought of kanji for them. Domu comes from the MS-09 Dom (ドム).
**Attacks involving the use of one's own body as a direct weapon. E.g. punches.