Staggershock [Mystery Booster] Nightmare Salamander Beast and it loses defender

and it loses defender

"My bet's on the dirt

Set: Revised Edition Type: Enchantment — Aura Rarity: Uncommon Cost: {2}{U}{U} Enchant artifact

Set: Scars of Mirrodin Type: Instant Rarity: Common Cost: {3}{G} You gain 1 life for each creature on the battlefield

Set: Mystery Booster Type: Creature — Jackal Warrior Rarity: Common Cost: {1}{G} You may exert Bitterblade Warrior as it attacks

Staggershock [Mystery Booster] Nightmare Salamander Beast and it loses defenderSet: Mystery Booster Type: Instant Rarity: Uncommon Cost: {2}{R} Staggershock deals 2 damage to any target. Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)