NeoXan is a legendary Runeword created by combining a Neo Rune of Ritual and a Xan Rune of Invocation.
How to Create NeoXan
You can create NeoXan by adding the rare Neo Rune of Ritual and the legendary Xan Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Neo - Avoid health damage while fighting for 2 seconds. (200)
Xan - Your next Skill cast will be a guaranteed Critical Strike and Overpower. (800)
Overflow
NeoXan can not overflow because the Xan Rune does not have an overflow effect.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.