Mr. Forester was a park ranger.
Mr. Forester is a middle-aged Caucasian male, with black hair and a thick mustache. He wore a ranger's uniform, and a hat as part of it.
Mr. Forester took his job as a park ranger way too seriously than he needed for obvious reasons, which would've made him a possible suspect to the gang.
A Pup Named Scooby-Doo
Forester had been working as a park ranger as a front for him trying to find diamonds at the mine. He dressed up like the Ice Demon to scare people away so he could get the diamonds he found. He took off only part of his costume in trying to cover his scheme, and when he tried to escape, Scooby used the ice shooter in his costume to freeze him in a block of ice and to turn him in to the police.