Advanced format ruling
Mask of Brutality
Card effect (current official text)The equipped monster gains 1000 ATK and loses 1000 DEF. During each of your Standby Phases, pay 1000 LP or destroy this card.
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.