I know after many maintenances through the past that certain creatures do not occur in the game. After some outages the enraged oaks have disappeared and after others the radiant wisps have disappeared. I know this is a continuing problem. After the maintenance outage of January 31,2017, the radiant wisps were doing fine for about an hour. For an hour they were normal then for an hour ALL radiant wisps (normal and enraged) just disappear. After another hour, they all reappear. This has been happening since outage. The shadow wisps in Doom are doing same thing. They are there for a time period and then they are gone for a time period. The granite at Augh. mines by the stone shop is doing the same thing. One hour there is granite and then all of a sudden it is all gone. I do not know what is causing this but it is a pain. Thank you. Slimey on Order