Problely better as this:
“Search your library for Red or White Alicorn Creature, reveal it, put it into your hand, then shuffle your library. Celestial Birth Deals X Damage to Target creature. If that creature dies this turn, add to your mana pool any combination of (W) and/or (R) equal to it’s converted mana cost. Exile Celestial Birth.”
“Search your library for Red or White Alicorn Creature, reveal it, put it into your hand, then shuffle your library. Celestial Birth Deals X Damage to Target creature. If that creature dies this turn, add to your mana pool any combination of (W) and/or (R) equal to it’s converted mana cost. Exile Celestial Birth.”



