Tsarina Signet urges Carl to hurry because her summoned battle squad will fade soon. Carl asks for a promise that Donut will be freed if he dies, then enters the big top alone with the circus ticket. Inside the entrance tunnel, a level 9 clown named Clammy the Clown confronts Carl, but the ticket functions like a pass and the clown lets Carl through instead of attacking.

Once inside, Carl is overwhelmed by the circus smell, which triggers a vivid memory of going to a small circus with his mother when he was four. The memory makes Carl realize how much of his mother he has lost and how violently this place has corrupted one of the few happy associations he still had. That rage briefly makes Carl want to abandon caution and destroy everything, but thinking of the unconscious Donut and Mongo outside forces Carl to steady himself and continue with the plan.

Carl notices that the performers are still acting out grotesque versions of their old routines, as if the battle outside never happened, and none of them react to him while he holds the ticket. He sees a sign welcoming visitors to Ringmaster Grimaldi’s circus, then finally recognizes that the giant plant filling the center ring is the true target. An achievement reveals that Carl has discovered a city boss, and inspection identifies Ringmaster Grimaldi as a level 85 elite Pestiferous Vine that keeps the circus family alive and repeatedly resurrected. Carl also spots the infected ogre Apollon the Mighty and realizes the vine’s control reaches throughout the tent.

Carl remembers Mordecai’s explanation that a Pestiferous Vine can be killed if poisoned blood is dripped directly onto it, though the effect takes time and can be reversed if the vine receives matching antidoted blood. Even after realizing he is facing a city boss and could still retreat, Carl decides to gamble on the plan. He sits beside one of the roots, removes his nightgaunt cloak so his poison resistance drops, uses health potions to poison himself, slices his palm with a juggling knife, and squeezes blood onto the vine. After healing the cut and taking an antidote, Carl sees that the vine has absorbed most of the blood, but nothing changes immediately, leaving him unsure whether the attempt has worked.