Don ' t Come Back , it ' s a level 50 Falcon ' s Nest escort leve right outside town . You start it and fly down the path checking for the ~ 5 places a chest with an AmberEncased Vilekin in it can spawn . Just keep cancelling the leve and restarting it to farm Vilekin from the chests . Each Vilekin can be exchanged for a Sand . Super fast , and completely free . Spawn rate on chests is approximately 30 %, so you ' ll probably blow through about two full sets of 99 leves before you get all the sands you need . People are likely downvoting me because they ' re worried SE will nerf it , but it ' s been public knowledge since that step of the weapon went live and they haven ' t touched it . If they haven ' t touched it so far , it ' s doubtful they will .