Most Information and Bio picture are from Xbox360Achievements.org and its posters xRogue 5x and Fizzmatix. Original thread can be found at this location.
The Polar Slimer appears in Ghostbusters: The Video Game in the multiplayer missions. It is a Most Wanted Ghost. It is an artic variation of Slimer and will appear if the player has captured Wee Slimer and dunked Slimer 20 times in the Slime Dunk jobs.
As of summer 2010 a glitch in the Xbox 360 version of the game has made Polar Slimer unobtainable. Terminal Reality released a statement in June of 2010 on their Facebook page that a patch to fix the glitch will be released in the upcoming fall along with a firmware update.