The Masked Beast (LON-EN001) - Labyrinth of Nightmare (Worldwide English) Unlimited Defense_2150 Card TextThis card can only

Card TextThis card can only be Special Summoned by the effects of A Deal with Dark Ruler

except "Dupe Frog"

Card TextAll Fish

Card TextAt the end of the Battle Phase

while this card is in your GY: You can Special Summon this card

The Masked Beast (LON-EN001) - Labyrinth of Nightmare (Worldwide English) Unlimited Defense_2150 Card TextThis card can onlyTypeFiend Ritual Monster AttributeDARK Level Rank8 ATK DEF3200 1800 Card TextThis monster can only be Ritual Summoned with the Ritual Spell Card, Curse of the Masked Beast. You must also offer monsters whose total Level Stars equal 8 or more as a Tribute from the field or your hand.