Celestial

Celestial is the Healer power set included the the Sons of Trigon DLC.

A developer confirmed Celestial as the Healer power set included in the Sons of Trigon DLC on July 26, 2013:

Hey folks, Celestial is the new power coming in Sons of Trigon. I can assure you it is not very much like Sorcery, and we'll have a lot to share on the subject in the coming weeks. For clarification and a little more detail, you will want to tune into tonight's Friday Night Legends (4PM Pacific). It will be out of this world.

https://forums.station.sony.com/dcuo/index.php?posts/1915855/