River of Forgetfulness!
Gu Xi raised the Illusion Magic Staff and pointed straight ahead.
The Underworld Master's skill, River of Forgetfulness, was unleashed by Gu Xi on the spot.
The River of Forgetfulness was, in essence, a skill that released water outward.
Normally, Gu Xi only released it once in a while over at Heavy Breath Mountain.
He rarely used it properly on a major battlefield.
After all, the River of Forgetfulness was mainly known for its corrosive river water, not for the volume of water it produced.
But in the situation before him, the River of Forgetfulness's current, capable of corroding everything—even swallowing undead—was the most useful of all.
On the surface, the World Tree looked incomparably solid.
But in truth, the World Tree was the same as the Elves. Because of its immortality, the inside of the World Tree had actually already rotted away.
It was just that the World Tree's exterior was extremely hard, so its condition could not be seen for now.
However, when Gu Xi had seen this World Tree earlier, he had clearly felt a rotten aura rushing toward him.
If there were no problem inside, that would have been strange.
As Gu Xi released the River of Forgetfulness outward, the river water rushed straight onto the World Tree.
The river water struck at the World Tree's roots and trunk.
Under one wave of impact, the parts of bark hit by the river water rotted away on the spot.
And from within the World Tree, a kind of green liquid flowed out.
Anyone who did not know better might have thought this was the World Tree trying to save itself.
In truth, all of it was the parts of the World Tree that had already decayed.
Previously, all of these things had been stored