At the beginning of your upkeep, destroy target nonland permanent with the lowest mana value. (If two or more permanents are tied for lowest, target any one of them.)
Legalities
Not Legal
Standardbrawl
Brawl
Future
Pauper
Alchemy
Pioneer
Historic
Standard
Gladiator
Oldschool
Premodern
Historicbrawl
Paupercommander
Explorer
Timeless
Legal
Duel
Penny
Legacy
Modern
Vintage
Commander
Predh
Oathbreaker
Rulings
2004-12-01
If the lowest converted mana cost is 3, Culling Scales can destroy itself.