This is Commodore 64 code and memory debugger that works in real time. It is quick prototyping tool where you can play with Commodore 64 machine and its internals.
>Shadow of the Beast is a side-scrolling platform computer game produced by Reflections and published by Psygnosis in 1989. The original version was released for the Commodore Amiga, and was later ported to many other systems. The original Amiga release cost £35, an unheard of price for a video game in that era, but it did include a T-shirt in the box bearing a print of the box’s artwork.