Bljorin, Ancient Gaurdian

Wheneaver one or more creatures you control
attack you may reveal Bljorin, Ancient Gaurdian
from your hand or if he is on the battlefield
or in the command zone, you get a woodland
counter.
Wheneaver Bljorin, Ancient Gaurdian enters
the battlefield you get an emblem with, Pay 1 woodland counter, add one mana if any color to
your mana pool, spend this mana only to cast
creature spells.