Rulings

• 2020-04-17
  Parasitic Impetus causes you to gain life, not the attacking creature's controller.
• 2020-04-17
  If you are the attacking creature's controller, you lose 2 life and gain 2 life. You won't lose the game if your life total is 0 in between these two events.
• 2020-04-17
  If a goaded creature can't attack for any reason (such as being tapped or having come under that player's control that turn), then it doesn't attack. If there's a cost associated with having it attack, its controller isn't forced to pay that cost, so it doesn't have to attack in that case either.
• 2020-04-17
  If a goaded creature doesn't meet any of the above exceptions and can attack, it must attack a player other than a player who goaded it if able. It the creature can't attack any of those players but could otherwise attack, it must attack an opposing planeswalker (controlled by any opponent) or a player who goaded it.
• 2020-04-17
  Attacking with a goaded creature doesn't cause it to stop being goaded.
• 2020-04-17
  Being goaded more than once by the same player is redundant.
• 2020-04-17
  If you goad a creature you control, it must attack and it must attack a player rather than a planeswalker.
• 2020-04-17
  If a creature you control has been goaded by multiple opponents, it must attack one of your opponents who hasn't goaded it. If a creature you control has been goaded by each of your opponents, you choose which opponent it attacks.