Xyz Material Xyz Materials ( pronounced ik - seez ) ( Japanese : " Ekushīzu Sozai " , エクシーズ in card text before " Duelist Alliance " ) , are cards stacked underneath an Xyz Monster . They are known as Overlay Units ( オーバーレイ ・ ユニット , " Ōbārei Yunitto " ) , abbreviated ORU , in the anime and manga . When an Xyz Monster is Xyz Summon ed , the monsters used for the Xyz Summon are stacked underneath the Summoned Xyz Monster . The attached Xyz Materials do not occupy a Zone . Many Xyz Monsters have effects that require detach ing Xyz Materials ( send ing an Xyz Material attached to that Xyz Monster to the Graveyard ) as an activation cost . If the Xyz Monster is no longer in a Monster Zone , any Xyz Materials that were attached to that Xyz Monster are sent to the Graveyard . Some card effects allow attach ing cards to Xyz Monsters as Xyz Materials ( placing them underneath the Xyz Monster ) through means other than Xyz Summon . Some card effects allow cards to be attached as Xyz Materials ( such as " Xyz Reborn " , " Overlay Regen " and " " ) . Unlike the terms Fusion Material Monster and Synchro Material Monster , the term " Xyz Material Monster " was never used . In addition , since July 2017 , most instances of effects unambigously referring to Xyz Materials now simply say " material " . Rulings . Xyz Materials underneath Xyz Monsters do not count as monsters , so detached Xyz Materials will be sent to the Graveyard even if " Dimensional Fissure " is on the field . While monsters are acting as Xyz Materials , they cannot be target ed nor apply their effects . Xyz Materials are not treated as being on the field , and also being attached as an Xyz Material is not considered to be the card leaving the field . Therefore , when an Xyz Material is attached or detached , any effects of the Xyz Material that only activate when it leaves the field ( such as " Reborn Tengu " ) do not activate . Token Monster s cannot be used as Xyz Materials , because Xyz Materials are attached to the Xyz Monster and attached Xyz Materials are not considered to be on the field . Even when attaching Xyz Materials with a card effect , Xyz Materials can only be attached to Xyz Monsters ( e . g . " Phantom of Chaos " that has copied the effect of " " cannot activate the effect to attach a card as an Xyz Material ) . Likewise , even with a card effect , Token Monsters cannot be attached as Xyz Materials . Historical rulings . Before it was clarified that Xyz Materials cannot be on the field , as an interim ruling , the " TCG " ruled that they were on the field ( whereas the " OCG " consistently ruled that they were not ) . In the anime . In " Yu - Gi - Oh ! ZEXAL " and " Yu - Gi - Oh ! ARC - V " , as previously noted , Xyz Materials are instead called Overlay Units , and are depicted as orbs of light orbiting the body of the Xyz Monster , and glow with the color associated to the Xyz Monster ' s Attribute ( e . g . LIGHT Xyz Monsters have yellow Overlay Units ) . Additionally , during an Xyz Summon , the cards to be used as Xyz Material light up with the color associated of their own Attribute before briefly spiraling around each other and entering a bright swirl of energy called Overlay Network . When the player detaches Xyz Materials for their respective Xyz Monster ' s effect , the monster in question is shown to absorb them through several methods , such being eaten with their mouth or striking a weapon they carry . In some cases , the Xyz Monster will glow with the Attribute color for a few moments before unleashing the effect . Uniquely , the Xyz Materials of " C " monsters of Barian origin are depicted as magenta crystals that float stationary in front of or behind the monster , often lined up to each other . These are named Chaos Overlay Units ( abbreviated as " CORU " ) . When instead detached by another card ' s effect , the Units are drawn away from their orbit and dragged inside a purple Graveyard portal . In " ARC - V " , Xyz Materials are still usually absorbed by the Xyz Monster , but sometimes they are instead flung in another direction . A recurring example is the anime effect of " Raidraptor - Rise Falcon " , which allows it to gain the total ATK of all opponent monsters that were Special Summoned ; to symbolize this , the used Material is sent flying towards the field of the other player ( s ) . However , in general these animated effects tend to be much less elaborate than in " ZEXAL " , often simply causing the Material to disintegrate while still in its orbital path .