You may play this spell after you declare an Attack a Phoenixborn main action. Destroy X units you control. If you do, X target units you currently control gain the following abilities for the remainder of this turn:
Overkill X: When this unit destroys a unit an opponent controls by attacking, deal X damage to that opponent's Phoenixborn.
Spite X: When this unit deals damage to a Phoenixborn by attacking, you may deal X additional damage to that Phoenixborn.