That Dekan was most likely using an Armor Defense Zhen. He already has a lot of Pd to begin with by being full Vit, but it also boosts the PD you get from buffs and possibly scrolls. He can't have DD though, so he'd end up dying even faster than before with the AD weapon. Also, Attack is stronger than Defense. 1000 PD is not equal to 1000 Melee or Ranged Attack. This is why as people level up and get higher tier weapons and armor, they start hitting harder on each other, but the time to kill stays somewhat balanced because max HP increases as well. People these days would literally need thousands of points of Pure Defensefor things to balance out. This just complicates things even more, which is why its better to just remove the Attack.