Attempting to fire hungering skulls around a large burning pyre asset results in the flaming skulls disappear. Some testing seems to indicate the problem is with the burning pyre asset. The attached gif shows some of the testing.
e: Renamed from raging skulls to hungering skulls. Look, they’re red and fiery; that makes them angry. Also, was able to confirm this with a second pyre.
Mountain Aerie, Divine Era, Level 62.