Jord Who Shakes The Earth

{t}: add {g},{u}, or {r} in any combination to your
mana pool equal to the greatest power among
creatures you control.
At the beginning of the next end step, if
you don't control a creature with power 10
or more, transform Jord Who Shakes the Earth
If Jord Who Shakes The Earth dies, exile it
instead, then return it to the battlefield at the
beginning of your next upkeep.