To lift the curse and bring the people back you must kill the mage. He is immune to usual weapons, beware.
The Sword of Hrakel website by Lance Ewing, pulls apart and investigates the code of this adventure in order to discover its secrets; it includes a full walkthrough.
[+] Users who have solved this game
[+] Users currently playing this game
A good game, harder than you expected and kinda twisted. Highly recommended.
You can download it here for the Vic20+8K ram expansion: https://www.mdawson.net/vic20chrome/vic20/gamebase/vic20/games/Sword%20of%20Hrakel.zip