The rumble of the earth was enough to shock them when everyone realized that the guardian vine and root had made a lot more changes than what they could see above ground. large intertwined roots tore through the earth and reared up toward the sudden flurry of arrows that Gil fired from a distance.
This major distraction had been the original plan so that they could push forward. But since they were not watching such a large scale response, Walker temporarily held the fire ball he had made back. The same with the other elves and their arrows.
"It made itself a complete safe area!" This wasn't what a plant should be able to do. Alma knew that she had never seen a plant capable of this. If a single seed were to be found, she needed it. It could be an immense method of growth for her.
The more that they watched the roots rear up, the more that they all realized they were watching the guardian plant and root stand up for the lost part.