Engineered Plague (Antoine Ruel) (SB) [World Championship Decks 2001] 199 that player adds one mana

that player adds one mana of any type that land produced

If this card battles

Set: Limited Edition Alpha Type: Enchantment — Aura Rarity: Uncommon Cost: {2}{B}{B} Enchant land

Set: Amonkhet Invocations Type: Enchantment Rarity: Mythic Cost: {2}{U}{U} Tap an untapped creature you control: Tap target artifact

other than "Elemental Hero Neos"

Engineered Plague (Antoine Ruel) (SB) [World Championship Decks 2001] 199 that player adds one manaSet: World Championship Decks 2001 Type: Enchantment Rarity: Uncommon Cost: {2}{B} As Engineered Plague enters the battlefield, choose a creature type. All creatures of the chosen type get 1 1. A single germ can kill more soldiers than ten thousand blades.