Searching for an early-mid-90s young adult horror novel name

Question

I'm wracking my brain trying to remember the name of a book I read way back in grade 3 or 4 (maybe 5?); I know I purchased it through Scholastic book-order, and it takes place at a boarding school/prep school, and had some really nasty kills (I distinctly remember one character being decapitated while after slipping either on or nearby the school's ice hockey rink, and the description of the murder weapon - almost like a restraint that a dog-catcher would use to pick up a stray, some type of metal rope that can be tightened from a distance...)

On the cover was (I always believed anyway) the main character, in some type of "military" outfit, complete with large hat (seemed very Civil War-esque), and he's looking over his right shoulder while standing at attention as a grey or blueish hand is reaching towards his shoulder (the picture is closer to a portrait of the main character, but I'm almost positive you can see just past his shoulder line on the cover).

Anyone have any idea what I'm talking about? I haven't been able to find anything online even close to it...

Answer 1

I think this is Warlock Games by Richard Lee Byers. The blurb on the back:

At first Mark wants nothing to do with the rivalry. He's falling for Cooper High student, Laurie Frank, and doesn't want anything to get in the way. But when fellow Hudson cadet Greg Tobias urges him to fight back, Mark suddenly finds himself joining other cadets in playing weird and violent pranks on Cooper High. What Mark doesn't know is that Greg is a centuries old warlock who's playing a sick game with a fellow demon.

Also the picture on the front is similar to what you described- someone in a military style uniform with a rifle is standing in a forest and a giant, pale hand is reaching for him from behind.