Fusion Material Monsters (融合素材 Yūgōsozai), formerly formatted as Fusion-Material Monsters, are monsters that are used for the Special Summon of a Fusion Monster; the required Fusion Materials are listed on the Fusion Monster's card.
While Fusion Material Monsters are usually specific monsters, occasionally, the required monsters are more vague; such as "Five-Headed Dragon", simply requiring any five Dragon-Type monsters; or "Chimeratech Overdragon", requiring "Cyber Dragon" and one or more Machine-Type monsters.
Listed Fusion Material Monsters are monsters specifically named on a Fusion Monster as materials; non-specific Fusion Materials, such as those of "Ojama Knight", cannot be targeted by cards that specify listed Fusion Material Monsters such as "Centrifugal Field".
Fusion Substitute Monsters such as "King of the Swamp" can replace one named Fusion Material Monster. If a Fusion Substitute Monster is used, all other Fusion Material Monsters used in the fusion must be correct. However, monsters whose name is being treated as a listed Fusion Material Monster (e.g. "Elemental HERO Prisma") are treated as correct and not as Fusion Substitute Monsters. Fusion Substitute Monsters can only replace specifically named Fusion Material Monsters; as such, a Fusion Substitute Monster cannot be used in the Fusion Summon of "Evil HERO Dark Gaia" as it does not name any monsters, and can only replace "UFOroid" in the Fusion Summon of "UFOroid Fighter".
Fusion Material Monsters can be used even if the summon is not a Fusion Summon. Cards in the Hex-Sealed Fusion series tribute themselves and the other necessary Fusion Materials specified on a Fusion Monster to Special Summon it, but this Special Summon is not treated as a Fusion Summon. Contact Fusion is also a type of Special Summon that is not considered a Fusion Summon.
There are also several Monsters which cannot be used as a Fusion Material Monster.
- Fusion Monster
- Fusion Summon
- Fusion Deck
- Fusion Deck Zone
- Fusion Substitute Monster
- Cannot be used as a Fusion Material Monster