Mercy Killing [Shadowmoor] SPA Vengadora krosana Serum was once derived from

Serum was once derived from Mirrodin's blinkmoths

target creature loses all abilities and becomes a blue Frog with base power and toughness 1/1

They make funny little popping sounds when they die

Set: Legends Type: Enchantment — Aura Rarity: Uncommon Cost: {U} Enchant creature

Set: Ravnica: City of Guilds Type: Sorcery Rare Cost: {4}{B}{B} Until end of turn

Mercy Killing [Shadowmoor] SPA Vengadora krosana Serum was once derived fromSet: Shadowmoor Type: Instant Uncommon Cost: {2}{G W} Target creature's controller sacrifices it, then creates X 1 1 green and white Elf Warrior creature tokens, where X is that creature's power. "We will give you the peace you seek, though you may not yet know you seek it."