KinjiHakari

Hakari's domain is a pachinko machine. Literally. The environment becomes a gambling parlor, and Hakari has to hit the jackpot on the machine to gain his power-up. When the jackpot hits, and it hits more often than probability should allow. Hakari receives unlimited cursed energy and automatic reverse cursed technique for exactly four minutes and eleven seconds. During that window, Hakari is functionally immortal. His body regenerates from any wound instantly. Cut off his arm. It grows back. Stab him through the chest: the hole closes. The healing is automatic and continuous, requiring no conscious effort. He can take lethal damage every second for four minutes straight and walk out smiling. Consecutive jackpots extend the immortality window, and the domain's mechanics subtly favor Hakari's luck, making repeat hits more likely than pure chance would suggest.