Zerus

Zerus enters the battlefield tapped. {T}: Add {B}. At the beginning of your end step, if a Zerg creature you control died this turn, put a creep counter on target land. As long as you control five or more permanents with creep counters, whenever you tap a land you control with a creep counter for mana, it produces one additional mana of any color. Spend this mana only to cast Zerg spells.{/fontsize-28}