Jester's Cap [Ice Age] Dragon Set: Legends Type: World Enchantment

Set: Legends Type: World Enchantment Rare Cost: {3}{B} Whenever a player casts a spell

Set: Rise of the Eldrazi Type: Enchantment — Aura Rare Cost: {2}{G}{G} Enchant creature Enchanted creature gets +2/+2 and has "Whenever this creature attacks

Set: Limited Edition Alpha Type: Enchantment — Aura Uncommon Cost: {2}{G} Enchant creature At the beginning of the upkeep of enchanted creature's controller

If you can't

Whenever you cast a creature spell of the chosen type

Jester's Cap [Ice Age] Dragon Set: Legends Type: World EnchantmentSet: Ice Age Type: Artifact Rare Cost: {4} {2}, {T}, Sacrifice Jester's Cap: Search target player's library for three cards and exile them. Then that player shuffles their library. "Know your foes' strengths as well as their weaknesses." Arcum Dagsson, Soldevi Machinist