Advanced format ruling
Mythical Beast Cerberus
Card effect (current official text)Each time a Spell Card is activated, place 1 Spell Counter on this card when that Spell resolves. Gains 500 ATK for each Spell Counter on it. At the end of the Battle Phase, if this card battled, remove all Spell Counters on it.
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.