AhuThul is a legendary Runeword created by combining a Ahu Rune of Ritual and a Thul Rune of Invocation.
How to Create AhuThul
You can create AhuThul by adding the legendary Ahu Rune of Ritual and the rare Thul Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Ahu - Lucky Hit: Up to a [100|%|] chance against Injured enemies. (25)
Thul - Invoke the Sorcerer's , inflicting Freeze and Vulnerable onto enemies. (300)
Mystical Frost Nova
Overflow
AhuThul can not overflow because the amount of Offering you receive from the Ahu Rune exactly fills the required Offering of the Thul Rune.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.