Shenanigans

Yet, Bringïrr himself wasn't sure how this corrupted area here worked. It was different from all those he had experienced before. Normally it would be the Eternal Protector who would analyze how the corruption existed and spread. For someone 7 Tiers lower to say he found something was beyond belief. 

"A few things," Eldrian replied with a smile but refused to share them just yet. He was still working through his thoughts. 

'What is divine magic?' This was the biggest question on his mind and one he felt was the last piece he needed to figure out what was going on. However, he had enough to make a conclusion even without it. 

So far he knew that fire, nature, and divine magic caused massive damage to the undead. One might think that fire and divine did so due to the usual trope. Yet, why would nature magic then do extra damage? Why was it also effective against the undead?