Tekkai

Tekkai, also known as Iron Body, is a defensive technique from the Rokushiki, a fictional system of six superhuman arts in the One Piece manga and anime series created by Eiichiro Oda. Practitioners use Tekkai to stiffen their muscles and raise body density, effectively making their bodies harder and more resistant to impacts.

The technique is performed by tensing and shaping the muscles to create a temporary, dense shell of force. It provides enhanced protection against blunt force and can cushion or absorb blows, enabling the user to withstand stronger attacks. However, Tekkai significantly reduces speed and mobility, leaving the practitioner less able to dodge or maneuver. Advanced users may withstand more powerful assaults, but the defense is not invulnerable, and highly precise, swift, or energy-based attacks can still pose a risk.

Tekkai is primarily used by practitioners of Rokushiki, including several CP9 agents and other combatants in the series. In combat, it is often employed as a foundational defensive option or as a setup to counterattack with other Rokushiki techniques. Different levels or applications of Tekkai are depicted as trading some mobility for greater defensive hardening, highlighting the technique’s place as a calculated risk in high-stakes battles.