Because Grade 6 artifact battle armours were so rare, most people had never seen one before. The same went for Murong Yu; he had no idea what was going on, so he continued his attacks on Nie Li. He had no idea that his attacks were having no effect.
Aside from Nie Li’s Grade 6 artifact battle armour, his Thunder God’s Meteorite Sword was something special too. The lightning pillars that it generated were extremely powerful.
Not to mention that Nie Li was only at 4-fate. Even if he were only a 1-fate, he could totally play Murong Yu to death, just with his luxurious equipment.
However, the most sinister thing was that Nie Li intended to thoroughly defeat Murong Yu. He continuously sent lightning pillars through Murong Yu, making him scream as he suffered terribly.
That was too evil!