Advanced format ruling
Reshef the Dark Being
Card effect (current official text)This card can only be Ritual Summoned with the Ritual Spell Card, "Final Ritual of the Ancients". Once per turn, by discarding 1 Spell Card from your hand, take control of 1 monster on your opponent's side of the field until the end of this turn.
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.