"Why doesn't she plant the other side as well?" Celene was a bit puzzled. She thought Vila would be staying in the Alamir Mountain Range for a long time.
"Even nature doesn't demand trees to be planted on the rocky side." Hill said helplessly.
The Undead Tribe's life is far removed from nature, so it's normal for them to be confused. But for Celene, a deity who has watched the earth for hundreds of thousands of years, to ask such a question... When Vila initially agreed for the Undead Tribe to build the Great Wall at the top of the Alamir Mountain, it was because beyond that point, there was hardly any possibility for planting.
She came to reestablish the natural cycle and certainly wouldn't disrupt the inherent water and soil environment of Kalinsan.
Hill noticed from the start that Vila scattered many grass seeds near the Great Wall... and quite a few were planted on the Wall as well.