Tharen; King of Thornblades

If an artifact has been destroyed this turn
Tharen; King of Thornblades becomes a 5/5
until the end of the turn.
Elf creatures you control cost {1} less to cast.
{g}{g}{g}{g}{g}: Sacrifice Tharen. All elf
creatures you control gain +1/+1 until the
end of the turn.