Operation Clogged Drain

 a limited-time questline released on October 23, 2019. It the main questline of Act 1 of the Treehouse of Horror XXX Event, following the short quest intro Same Mistakes, New Plan.

End
Unlocks Malicious Krubb.

End
Unlocks Hugo or gives 12 Donuts.

"You've received 12 donuts!"

- System Message.

End
Unlocks Robot Homer.

End
Unlocks the Scary Dock with the Blinky Monster or gives 12 Donuts.

"You've received 12 donuts!"

- System Message.

End
Unlocks Zia Simpson.