Batman Arkham Asylum Back to Intensive Treatment Chapter 10

As Batman leaves the Botanical Gardens, Joker announces that he has supplied the angered Ivy with some of the Titan serum, which he injects into her, causing a pained, yet pleasured scream. This causes a large vine to block the door and force Batman to use the vents to navigate his way out. Joker is shocked nothing has happened, rhetorically asking if he should give her another injection. He does so and then comments Ivy doesn't get her name for nothing; he wanted her to turn into a "40 foot plant monster", but was unsuccessful. While Ivy laughs maniacally, rumbling comes all around Batman and once outside, he sees that Titan is having a different effect on her. She causes mutated plants to grow rapidly and to gigantic proportions, slowly covering the island and entangling its buildings while large, bulbous flowers appear everywhere that exude deadly spores.
After battling past Ivy's plants while heading back into Arkham Mansion, Batman learns from Aaron Cash that the only way to access Croc's lair is through a pathway in Intensive Treatment. After breaking into the building, and dealing with several of the Joker's "security guards" (Inmate impostors wearing stolen guard jackets), Batman backtracks through the facility, but starts hearing a voice and coughing again; Scarecrow is returning. He then has a hallucination where, the beginning of the game is seen again, but this time, Joker is taking him to Arkham. There, he shoots him dead after Scarecrow taunts him. Batman then awakens in a shattered nightmare world again created by Scarecrow and defeats him again by sheer will. Seeing that Batman is used to his fear gas, Crane injects even more toxin into him, causing Batman to see Joker's henchmen as skeletons attacking him. However, Batman once again breaks free of the illusion and is clutching Scarecrow himself. Amazed at Batman's will power, Scarecrow gives another injection, asking Batman what he is as the amount of toxic is enough to drive ten men insane. He flees to the elevator, planning to drop his fear toxin into the Gotham water supply. Batman pursues him directly into Croc's lair.