(Simply adding numbers isn't festive enough
Tails You Lose Type: Creature — Minotaur Warrior Rarity: Rare Cost: {2}{R}{R} Cumulative upkeep—Flip a coin
Set: Commander 2011 Oversized Type: Legendary Creature — Elemental Rarity: Mythic Cost: {G}{U}{R} Protection from white and from black
Set: Commander Masters Type: Creature — Dinosaur Rarity: Rare Cost: {2}{G} Ascend (If you control ten or more permanents
Set: Modern Horizons 3 Commander Type: Creature — Naga Cleric Rarity: Rare Cost: {2}{G} You may play lands from your graveyard
Planar Chaos [Secret Lair: Heads I Win, Tails You Lose] Friday Night Magic 2012 (Simply adding numbers isn't festiveSet: Secret Lair: Heads I Win, Tails You Lose Type: Enchantment Rarity: Uncommon Cost: {2}{R} At the beginning of your upkeep, flip a coin. If you lose the flip, sacrifice Planar Chaos. Whenever a player casts a spell, that player flips a coin. If they lose the flip, counter that spell.