If you want to avoid some confusion, I suggest saying Robot Deck for artifact decks (or not using this term), and robot typal for the creature type
Whenever one or more other creatures you control leave the battlefield, investigate
Next, we need to think about the distribution of cards per color, regarding mana values and card types
Red gives us access to two very good ones in Lava Spike and Lightning Bolt, and if we really want to dig deep we can find Bump in the Night or Exquisite Firecraft/Flames of the Blood Hand
Whenever an opponent casts a noncreature spell, they lose two life, and you gain two
Artifact Color tag templates(None) Color tag templates(None) Herald's Horn As this artifact enters, choose a creature type