Advanced format ruling
Royal Swamp Eel
Card effect (current official text)If this card is used as a Synchro Material Monster, all the other Synchro Material Monsters must be Fish-Type.
Current rulings for this card are maintained by Konami.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Advanced forum — sourced change requests get reviewed.