Light of the Astromancer is an ability used by High Astromancer Solarian in Tempest Keep: The Eye. Solarian randomly casts this debuff on someone in the raid. The debuff counts down for 6 seconds and then does 5000-6000 arcane damage to the tagret and anyone within 10 yards. This also knocks anyone it hits high into the air, causing 100% fall damage. The target does not receive fall damage.
Anyone with the debuff is clearly visible by the purple lightning they will be shooting out.
This ability can be thought of as an arcane version of Baron Geddon's Living Bomb but much more deadly.