Reg, Abyssal Explorer

+1: Look at the top 3 cards of your library. You may reveal an artifact card from among them and put it into your hand.
-2: Reg, Abyssal Explorer deals 3 damage to target creature. If that creature is an artifact, destroy it.
-7: Emblem- 'Whenever this creature attacks, you may sacrifice an artifact. If you do, it gains double strike until end of turn."