Kragg, the Earth's Bastion

Whenever Kragg, the Earth's Bastion enters the
Battlefield or attacks, create a green artifact
token named Kragg's Rock with "If this artifact is
sacrificed: deal 1 damage to up to 3 target creatures."
Sacrifice Kragg's Rock: choose one of these effects:
• Kragg, the Earth's Bastion gains +1/+1 and
Indestructible until end of turn.
• Destroy target Artifact.
• Return one Mountain from your Graveyard to
the Battlefield under your control, tapped.