Advanced format ruling
Thestalos the Firestorm Monarch
Card effect (current official text)If this card is Tribute Summoned: Discard 1 random card from your opponent's hand, then, if it was a Monster Card, inflict damage to your opponent equal to its original Level x 100.
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.