CemXan is a legendary Runeword created by combining a Cem Rune of Ritual and a Xan Rune of Invocation.
How to Create CemXan
You can create CemXan by adding the magic Cem Rune of Ritual and the legendary Xan Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Cem - Cast Evade. (75)
Xan - Your next Skill cast will be a guaranteed Critical Strike and Overpower. (700)
Overflow
When CemXan overflows, you receive the Xan Rune's overflow effect (Cast increases damage by 1% per 10 Offering) 0.07 times.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.