Carl checks Bonnie and confirms she is not a changeling before following her and Donut into Kane’s last floating house. Inside, the rooms show signs of chaos and violence, and Carl finds Commandant Kane’s mutilated corpse laid across the kitchen table beneath a blood-written lemonade sign. Bonnie, whose eyes are unnaturally dilated and whose shirt is soaked with blood, behaves as if nothing is wrong, offers them lemonade, and casually explains that Denise is one of the replacement pets Kane gave her after Sausage died.

While the house shudders in the air, Carl loots Kane’s body and gets gold, a watch, and a letter from Ghazi. The letter reveals that the Glass Wizard has the winding box, has learned how to open a portal, and threatens to throw the world into the void rather than let the ghost leave the temple. Bonnie then explains that when Denise gets angry, magic fails and the balloon sinks. The clockwork Mongos explode early, Carl’s magical gear and buffs shut down, Donut cannot heal Mongo with spells, and Mordecai warns Carl that they are likely entering a boss fight where magic and many item effects will not function properly.

The house seals itself, a three-minute timer appears, and the system announces a Borough Boss battle against Denise, the Feral Goose Mother. The rules explicitly remove both magic and ordinary physical damage, leaving Carl, Donut, and the injured Mongo to retreat upstairs while the falling house races toward impact. Denise attacks with razor teeth and brute force, Mongo is wounded badly, and Carl tries to create space by sending Donut into the bedroom above the kitchen to break a hole through the floor. Carl assumes Bonnie’s lemonade must be the key to the fight, especially because Bonnie remains strangely protected and obsessed with remaking it.

Back in the kitchen, Carl grabs the pitcher as Denise dives in after them, but the system interrupts him with an achievement that reveals the supposed potion is only lemonade and that the whole setup was a deliberate misdirection. Carl then realizes Denise’s health moved only when he hit her with items already in the house, such as a mug and the pitcher. From Denise’s description as an environmental, Carl deduces that Denise is immune to his own direct attacks and weapons but can be harmed by the environment around her.

Nearly out of time and badly hurt, Carl remembers Bonnie pointing toward the sink when asked why Denise killed Kane and understands what Kane had tried to do. Carl wrestles Denise to the kitchen sink and forces her head into the garbage disposal while Donut flips the correct switch. The disposal tears Denise apart just before the timer expires, the falling house stops, Carl’s buffs return, and Donut heals Mongo. A system notification announces that Kane’s quarters have been occupied, the Air Quadrant has been liberated, and crawlers from that quadrant can now travel freely to the others.