Conditioning
The conditioning technique was a little different from the ones that he had seen in the Apprentice Realm.
As far as he could seem, the reason for this stemmed from the fact that the Martial Body was able to acclimatize to stimuli that were harmful to them far better than the normal human body could. This too was a trait that the human body lacked, but the Squire evolution breakthrough process was one of the few things that could grant the body this ability even if it didn't have it before.
By subjecting certain parts of his body to the poison over and over again, using both healing potions and his own innate healing factor, he could eventually create a generation of cells in a localized area that possessed the ability to resist and contain the poison until the time he wanted it to.