You can see that the enemies do not spawn in as they would on other maps. There are large square sets of eligible spawn points surrounding possible rewards. Then on each possible reward location you can also see smaller rings of possible spawn points. Unlike other biomes there is both a maximum spawn range and minimum spawn range. The maximum range is 2200 units, and the minimum is 600. This effectively means that when you trigger a reward the inner circle will be inactive, and the spawns will come from the outer box until you move around. For example in the below picture, if Melinoe is at the yellow star, the green spawns are active and the red are inactive. Spawn distances are based on Melinoe's location, not the reward location.