Rules Text Contains: When you play Energy Vortex, choose target opponent.
At the beginning of your upkeep, remove all energy counters from Energy Vortex.
During chosen opponent’s upkeep, he or she pays 1 for each energy counter on Energy Vortex, or it deals 3 damage to him or her.
X: Put X energy counters on Energy Vortex. Use this ability only during your upkeep.
