This is GORILLA.BAS — the classic QuickBASIC example game of two gorilla’s tossing explosives at each other while standing on buildings.
Copyright 1990, by Microsoft.  I’ve tweaked just a few tiny bits and pieces to make it build with QB64.  Archive contains the slightly tweaked original source and a Linux binary.
It’s not perfect.  The REST() function had to be tweaked (in order to be QB64 compatible) and that results in the animations not being 100% right… but it works!
If you like this, you probably want to be reading The Lunduke Journal.  You can read the details for this over there as well.