"CXyz" an abbreviation of "Chaos Xyz", abbreviated "CX" (
These monsters are created by the heralds of Barian World for the sole purpose of subduing the "Number" monsters, but OC Duelists have been able to create their own "Chaos Xyz" monsters for whatever purposes they choose.
Xyz Materials attached to "CXyz" monsters vary in appearance, but are colloquially referred to as "Chaos Overlay Units". Like monsters that can utilize Chaos Xyz Evolution, these monsters require an additional Xyz Material but with 1 higher Level in a regular Xyz Summon, since they themselves are 1 Rank higher than their respective original counterparts.
So far, all of the canon "CXyz" monsters, except "", can inflict effect damage. Visually, they tend to be tied together by the presence of glowing red energy on their bodies, energy from the , though this is not always the case for fanmade "CXyz" monsters.
Like the "Number C" monsters, they also had members that can be summoned without Ranking Up, but they usually have the same ATK and DEF as their base forms, and their also a life point restrictions, which usually required the player to have 1000 or less Life Points before they get to activate their effects.