Shattered Minds

A 7 day deadline, 4 best friends, Locked in their abandoned old school, all power has been shut off and the only things their phone can play is a message by a mysterious stranger that tells them they have to fight for their survival, so one, two, three only one can survive. The blood will shed and minds will shatter into tiny bits of broken glass. This hell is unwanted by them, all different years, a year 8, year 10, year 11 and year 13. Who will survive? Can they live on afterwards? Maybe they will all die. Who knows, truly?