During a time when Wiccan and Hulkling were questioning whether they were going to stay in space or begin to visit Earth more, Agatha Harkness decided to secretly test Wiccan’s abilities, unbeknownst to the boys.
Eidolon first appeared as the boyfriend of Wiccan in a dream-like pocket dimension. Wiccan appeared to be unaware of any changes and did not remember Hulkling, or any of the other previous events in his life.
While Hulkling was in space with his alien boyfriend, Wiccan and Eidolon seemed to be in a relationship. However, much of Wiccan’s time was spent trying to find a spell in which he could bring Eidolon back to life.
During one of the attempts at bringing him into the real world, Wiccan is woken up from the trance, remembering Hulkling and the rest of his life. Although Eidolon pleaded for Wiccan to stay, Wiccan decided to leave and reunite with Hulkling.
After Wiccan and Hulkling reunite, Agatha Harkness reveals to them that they were in a pocket dimension created by Wiccan himself. After both of them go back to their original Universe, Eidolon can still be seen alone in the pocket dimension, clearly missing Wiccan.