Droplet of the Crystal Sea

Sacrifice Droplet of the Crystal Sea: Name a card. You may spend mana as though it were mana of any color to cast the named card until end of turn.
"In a brief second, I felt attuned to the mana of this strange land and was able to call my full abilities. A shame it was wasted in that moment, I would have loved to study it further."
-Tamiyo