Zaen got relentless in attacking his target. He did not spare even a fraction of a second before trying to mess Aldo up. But just like Aldo had mentioned earlier, the more Zaen hurt him, the quicker he recovered. And as a result of fighting Aldo for so long, slowly led to reducing Zaen's stamina.
Aldo's healing was a pain in the butt for Zaen to handle. But he had no other choice but to keep trying and attacking him, in the hopes that his attacks would eventually be able to break through the healing. But so far, it wasn't happening.
Zaen was drenched in the blood of his opponent, yet there wasn't a single scar on Aldo's body anymore. Nothing Zaen came up with worked on Aldo. He tied to burn him, stab him but nothing. After a while, Zaen was finally forced to take a breather. But he wasn't the only one in need of a break. Although Aldo's accelerated healing was the thing keeping him alive, it came at a price, the price of endurance.