Guul Draz Overseer [Battle for Zendikar Prerelease Promos] Plains Set: Nemesis Type: Enchantment Rarity:

Set: Nemesis Type: Enchantment Rarity: Uncommon Cost: {4}{W} Whenever a creature you control blocks

Set: Theros Type: Creature — Siren Rarity: Uncommon Cost: {U}{B} Flying

Set: Friday Night Magic 2003 Type: Instant Rarity: Rare Cost: {1}{B} Destroy target creature with mana value 3 or less

Set: Starter 2000 Type: Creature — Rhino Beast Rarity: Rare Cost: {4}{G}{G} You may have Rhox assign its combat damage as though it weren't blocked

The lesson is clear

Guul Draz Overseer [Battle for Zendikar Prerelease Promos] Plains Set: Nemesis Type: Enchantment Rarity:Set: Battle for Zendikar Prerelease Promos Type: Creature Vampire Rarity: Rare Cost: {4}{B}{B} Flying Landfall Whenever a land enters the battlefield under your control, other creatures you control get +1 +0 until end of turn. If that land is a Swamp, those creatures get +2 +0 until end of turn instead.