The progress made cleaning up the homes and the damage from the ice was substantial. It had barely taken a full day with the assistance of the pure ice demons clearing the ice that built up. Not to mention the additional soldiers that came to clean along with various builders already on the island.
This was what led Walker to bring the, now thirty, pure ice demons. It seemed that Aie, the strongest, was not as well versed in their surviving numbers as Walker had expected. But it was easily explained that some of their people had not even bothered leaving their icy homes because they preferred to gather the mana.
This was just the level of their growth and how they lived. Some times they would go months without seeing another of their kind. There were even tales of the longest meditating pure ice demons appearing and finding that their entire village had moved without them.