The Baby Grinch's Mischief Whistle can be obtained as a drop from the Ice Queen in the Frost Moon on Wave 15 onwards. It summons the Baby Grinch pet.
When catching up to the player, it is carried by a little red balloon on a string.
- The Baby Grinch's Mischief Whistle will occasionally summon two of this pet. This can be fixed by using the whistle again.
- Added to the game.