Ent Stone Caster

{2}{g} Regenerate Ent Stone Caster.
When Ent Stone Caster enters the battlefield you may untap target Forest you control.
If Ent Stone Caster becomes the target of a instant or sorcery with {r} in it's mana cost sacrifice Ent, it cannot be regenerated.
Come my friends! The Ents are going to war...