Advanced format ruling
Hyper Hammerhead
Card effect (current official text)At the end of the Damage Step, if an opponent's monster that battled this card is not destroyed: Return that opponent's monster to the hand.
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.