Burning Spore, Theran

Empyrean - (At the start of the game, if this is
outside of the game, or in your sideboard, this counts
as an Empyrean.)
Menace
At the beginning of your upkeep, reveal the top
card of your library. If it's a creature, add {g} to
your mana pool equal to half its power at the beginning of your precombat main phase.