UrQax is a rare Runeword created by combining a Ur Rune of Ritual and a Qax Rune of Invocation.
How to Create UrQax
You can create UrQax by adding the magic Ur Rune of Ritual and the rare Qax Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Ur - Your Minion or Companion kills an enemy or dies. (10)
Qax - Your next non-Basic Skill cast spends all of your Primary Resource to deal up to 100% increased damage. (400)
Overflow
UrQax can not overflow because the amount of Offering you receive from the Ur Rune exactly fills the required Offering of the Qax Rune.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.