The forest had indeed been destroyed, but it was not through the efforts of the heroes alone, the majority of the destruction came from the [corrupted eldritch dragon] that had been hiding inside of it as it fought against them and the captains.
"Eris!" Bruce created a barrier and abandoned it as a decoy as several dozen tendrils crashed into it one after the other, flattening trees and catching everything ablaze with corrupted flames.
"Keep your focus on the monster, Bruce!" Eris placed her hand over her shoulder and performed [Heal] on herself after she had been swatted by a stray tendril.