Hardening

Hardening is a Quirk used by Eijirou Kirishima.

Description
The Quirk allows Eijirou to harden his body. It can be used as both the strongest defense and the strongest attack.

However, the upper limit of the Quirk is seen to be physical fatigue accumulated by the amount of damage taken, as shown in the Sports Festival Battle between Eijirou and Katsuki where the latter used a series of Explosion attacks to cause further damage to induce fatigue on Eijirou.