ZanXal is a rare Runeword created by combining a Zan Rune of Ritual and a Xal Rune of Invocation.
How to Create ZanXal
You can create ZanXal by adding the magic Zan Rune of Ritual and the rare Xal Rune of Invocation to a two-socketed 
Helm, 
Chest Armor, 
Pants, or 
Two-Handed Weapon.
Overflow
When ZanXal overflows, you receive the Xal Rune's overflow effect (Increased Duration) 0.5 times.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.
Legions
Helltide