Haunted House / Swampy's Lair

The Haunted House in Frogger's dimension appears as a decaying, wooden mansion, but additionally houses the underground lair of Swampy the crocodile, which Lillie Frog once fell into via a trapdoor activated by the front door's knocker ("Frogger 2: Swampy's Revenge"). The interior of the house consists of collapsing floors, hordes of ghosts, and various other haunting apparitions; beyond the regions of the house itself, however, there exists an elaborate setup where Swampy performs the vital aspects of his schemes, surrounded by flowing lava, spewing fire, and his own provided machinery. Originally, both the lair and the entire house had exploded, thanks to the efforts of Tad (who essentially saved everyone that day), but has since been reconstructed by Swampy, who just barely escaped the blast.

In the "Dimension" saga, Swampy provides his lair to Doctor Eggman, with whom he joins forces to defeat their common enemies. The alliance of heroes is brought to the Haunted House, which serves as a prison for them as they are captured and subjected to torture—almost. The Skirmish in Swampy's Lair involves Sonic, Calvin, Dib, and Knuckles managing to liberate all of their allies and sabotage Swampy's equipment once more, before making their escape outside (by breaking a window) and stealing one of the Doctor's vessels to flee the crocodile's lair.

The only piece of machinery not ultimately sabotaged, however, is the mainframe, which Frogger one day returns to as he notices a flashing red light from within the Haunted House. He enters Swampy's lair once more, and sees firsthand the makings of the "End Reality" Scheme, evident in the crocodile's conversations with a "correspondent," as seen on the mainframe itself. Later on, Bill, Treeby, and Tank return to use Swampy's equipment for contacting those on Blorch, before leaving the underground lair behind to ambush the crocodile on his own space station.