Tengu format ruling
Beastking of the Swamps
Card effect (current official text)You can substitute this card for any 1 Fusion Material Monster. When you do this, the other Fusion Material Monster(s) must be the correct one(s).
Rulings
(1) You can substitute this card for any 1 Fusion-Material Monster. When you do this, the other Fusion-Material Monster(s) must be the correct one(s).
- The (1) effect does not have any classification. It is not an Ignition, Trigger, Quick, or Continuous Effect.
- This effect does not target.
- Using King of the Swamp as a Fusion Material does not start a Chain Link.
- The effect You can substitute this card for any 1 Fusion Material Monster of a monster like King of the Swamp or Goddess with the Third Eye is not applied while the monster is in the Deck.
- When Special Summoning Chimeratech Fortress Dragon or XYZ-Dragon Cannon, you cannot send to the GY a monster like The Dark - Hex-Sealed Fusion as a substitute for a Fusion Material.
- If King of the Swamp is selected for the effect of Prohibition, you cannot use either of its effects.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.