Frontier Siege [Tarkir: Dragonstorm Commander]

Set: Tarkir: Dragonstorm Commander Type: Enchantment Rarity: Rare Cost: {3}{G} As this enchantment enters, choose Khans or Dragons.• Khans — At the beginning of each of your main phases, add {G}{G}.• Dragons — Whenever a creature you control with flying enters, you may have it fight target creature you don't control.