When you maintain your combat focus, your clarity of purpose and relentless drive allow you to overcome your body's frailties. Minor wounds heal in a matter of seconds, and you quickly recover from even a grievous blow.

Combat Focus, WIS 13

While you maintain your combat focus, you begin to accumulate 2 temporary hit points each turn. If you have three or more combat form feats, the benefit of this feat improves to 4 temporary hit points each turn. The temporary hit points disappear when your combat focus ends.