If this card is in your GY: You can banish 1 LIGHT and 1 DARK monster from your GY, except "Chaos Betrayer"; Special Summon this card is Defense Position, but banish it when it leaves the field. If this card is Special Summoned: You can target 1 card in your opponent's GY; banish it. You can only use each effect of "Chaos Betrayer" once per turn.
Special Summoned in defense position so cannot be used to push damage.
Banished when leaving the field after being revived by own effect.
You can use this revived monster as synchro material or tribute fodder.
Remove a card with a card with a graveyard effect, such as The White Stone of Ancients and Shiranui Spectralsword, to prevent your opponent from using it.
An archetype that is good at setting up the graveyard. If you play Twilightsworns or the Zombie-Lightsworn mix, Chaos Betrayer will have the LIGHT and DARK monsters it needs to revive itself. Chaos Betrayer can then be used as synchro material with Tuners such as Glow-Up Bulb or Plaguespreader Zombie.