The cassette label indicates that this is a pretty fabulous adventure. However, I suspect you would get greater thrills out of re-reading an Agatha Christie novel for the fifth time.
You start out in the Gardens of Perilous - lots of trees and lumps of ruined masonry, with the odd sword, cup etc lying rather conspicuously about.
"You" are a little geezer of indeterminate sex in a yellow hat, who walks quite realistically but very, very slowly around in response to the joystick. You have 98 life points at kick-off, which you gradually lose as you enter new rooms, walk into a wall or tree, or get attacked by the demons - Phobos and Deimos.
Phobos, who both munches your life points and dumps you back at the start of your current maze, is a sort of flying purple square. Deimos, who's bothered only about your life points, is a rudimentary dickybird. They're exceptionally easy to avoid. Finding your way around is also easy.
You can get killed by doing silly things such as picking up a second sword. They come in light and dark varieties and you aren't supposed to mix the top.
Barring silly errors, you will find a gate through which you trot with your four treasures to the next. A labyrinth of caves once again filled with swords, cups, etc, plus a few goodies such as a lead suit and sets of keys. Oh, and a chest that's booby-trapped, but very obligingly tells you so. There is a radioactive room that's as safe as houses once you have your leaden suit, and so on.