Frogkin Kidnapper

• WWizards of the Coast2019-11-12
  Official Ruling
  Pay no attention to any other card in this set using the word “ransom” when determining how Frogkin Kidnapper’s ability works.
• WWizards of the Coast2019-11-12
  Official Ruling
  Paying to get a ransomed card back is a special action. The card’s owner may pay that cost any time they have priority, and players can’t take actions in between the time the player announces their intent to pay and the time the card returns to the zone from which it came.
• WWizards of the Coast2019-11-12
  Official Ruling
  The exiled card’s owner may pay its ransom cost even if the permanent that ransomed it leaves the battlefield.

Rulings via Scryfall