Advanced format ruling
Supersonic Skull Flame
Card effect (current official text)This card cannot be Normal Summoned or Set. This card can only be Special Summoned by removing from play 1 "Skull Flame" from your Graveyard. Once per turn, you can inflict 400 damage to your opponent for each "Burning Skull Head" in your Graveyard. When this card is sent from the field to the Graveyard, you can Special Summon 1 "Skull Flame" from your Graveyard.
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.