XolQue is a legendary Runeword created by combining a Xol Rune of Ritual and a Que Rune of Invocation.
How to Create XolQue
You can create XolQue by adding the legendary Xol Rune of Ritual and the rare Que Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Xol - Invoke a Skill from another Class. (150)
Que - Invoke the Druid's for 3 seconds, granting yourself a Barrier. (300)
Earthen Bulwark
Overflow
XolQue can not overflow because the amount of Offering you receive from the Xol Rune exactly fills the required Offering of the Que Rune.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.