Steelborn Iron body
The Steelborn Iron body is an Iron body focused on strength, used by Yerin Arelius and her master the Sage of the Endless Sword.[1] Ruby also gains the ability to use the Steelborn body to an extent, though it is weaker because she doesn't have a real body.[2] The Steelborn body allows its user to channel their madra into it to improve their physical power.[3] Yerin describes it as being "the best Iron body in the world for pure brute strength" on advancement to the Lord realm, though it is relatively weak before that.[1] The Path of the Endless Sword does not have a very good full-body Enforcer technique, making the Steelborn body a good choice to cover for its weaknesses.[4]
It is attained by being submerged underwater, breathing through a reed, for some time prior to advancement. Like other Iron bodies, the longer the ritual is undergone, the greater its effects will be for the user; Yerin spent three days and three nights in a pool in preparation for advancement.[1]
