"Skull Cracker can be considered the spiritual successor to the 1991
title [Creepy Castle][1] that Bill Appleton wrote for Reactor Inc. The
game is set in an alternate world where it is normal to see zombies
and monsters roam the streets. They are kept under control by MEI
(Mortality Enforcement, Inc.) - an organization that "helps the dead
stay dead". As the monsters grow in number however, they organize
themselves and demand civil rights. Since they are a common sight and
fairly harmless, people do not worry about them, but a mysterious
substance known as Goop changes the monsters' character drastically.

MEI brings in the freelancers Mortis "The Skullcracker" Rigor and
Penelope "Bonebreaker" Jones to bring back order. Players can choose
between one of the two characters, each with a distinct fighting
style. With side-scrolling brawling gameplay, they need to travel
through four main locations of four levels each. Some of the places
visited are a shopping mall, an arcade, the graveyard, a playground,
the MEI headquarters, and more. Next to moving, jumping, and climbing,
they can punch and kick opponents, and use power-ups such as flare
guns, flame throwers or supersoakers filled with holy water to take
out enemies, while replenishing health with pick-ups."
--[MobyGames.com][2]

2nd DL above: is a hybrid Mac/PC .iso image, compressed with StuffIt
5.5

Compatibility
Architecture: 68k PPC

68040 or PPC
System 7.1 or later
8MB RAM
256 Colors
Double Speed (2x) CD-ROM drive

  [1]: http://macintoshgarden.org/games/creepy-castle
  [2]: http://www.mobygames.com/game/skull-cracker