https://frederick352.itch.io/alien-planet-underwaterc-research-sea-of-horror

This is second game in series "Alien planet underwater research". In first quest you need to find a rocket, destroy barrier and use portal. You can also collect treasures and search for hidden paths. You can also find a poster and a message, In second quest you need to save alien Jinx. And you should beware hostile underwater creatures. My 7th zx spectrum game.