Mystic Haunt Zone

Mystic Haunt Zone is the fifth level in the PSP game Sonic Rivals 2. It is a graveyard themed zone featuring collapsing floors, acres of graveyard real estate and even ghostly copies of Sonic and Tails. The boss is the Egg Phantom.

Sonic and Tails
Sonic and Tails are confronted at the very beginning of the zone by ghostly simulacra of themselves. Defeating these malevolent shades is the work of their Acts 1 through 3. At the boss, Sonic (still unaware that they've been pursuing a disguised Eggman Nega) attributes "Eggman's" strange mannerisms to ghostly possession.

Shadow and Metal Sonic
Shadow and Metal Sonic, approaching the area, are informed by Eggman that the Zone (as with Sunset Forest Zone) will make it difficult for him to relay orders. The fat man orders Metal Sonic to pursue Knuckles and Rouge, determined to prevent the bat from collecting all the Chaos Emeralds for Nega. Shadow, meanwhile, races to find Mystic Haunt's gem before Rouge does.

Knuckles and Rouge
Knuckles is led to Mystic Haunt by Rouge, who's been directed there by her mysterious client. Once again, the emerald detector runs out of Rings, so Knuckles races off to find more. Rouge spots Espio, who she misconstrues as the person who hired her and sets off in pursuit.

Silver and Espio
Silver and Espio find Eggman Nega in Mystic Haunt Zone. Eggman Nega claims to be holding a roomful of Chao in the haunted castle, and he wants to feed them to the Ifrit to give it power. The duo sets off to save the Chao. After the Chao have been saved, they follow Eggman Nega through a portal into Chaotic Inferno Zone.

Trivia

 * Instead of each team paired with another as rivals, Sonic and Tails face ghost versions of themselves while all three of the other teams are each others' rivals.