Ticking Mime Bomb

• WWizards of the Coast2022-10-07
  Official Ruling
  To pantomime means to act out or express something in an exaggerated fashion without speaking. You're trying to get the outside person to guess the creature based on your expressions and movements. You can't just point to the creature you want them to pick.
• WWizards of the Coast2022-10-07
  Official Ruling
  If the outside person chooses one of your creatures, consider briefly why you didn't fully explain to the outside person what's going to happen, and ask them to choose a creature you don't control.
• WWizards of the Coast2022-10-07
  Official Ruling
  Count the number of Robots you control as the ability resolves to determine how much damage to deal. If Ticking Mime Bomb is still under your control and still a Robot, it will count itself. Quietly.
• WWizards of the Coast2022-10-07
  Official Ruling
  You aren't allowed to speak while pantomiming, but you can explain to the outside person what's going to happen before you begin as long as you don't try to give them hints about which creature to pick.

Rulings via Scryfall