I'm trying to remember a Tandy CoCo 2 fantasy adventure game, from somewhere in the 1980s. It was a largely puzzle-based game. I don't remember any combat in it, just puzzles that you had to solve with the items you found. It started out with you on a mountain top, having to confront something at the gap between two rocks. Somehow, that resulted in you being up in a tree-top with the way out blocked by a fire.
I remember the solution involved warding off a snake (I don't remember how) and using a bucket lowered on a rope to fetch water to put out the fire. Somewhere after that was the first timed puzzle of the game. I remember you had to light a torch to burn a rope to make something swing towards you, but you also needed that torch to fend off the green slime at the bottom part of the map to get to the next section, and it only lasted for a few seconds.
After that, I don't clearly remember things. Some of my memories are from watching my older brother play. I know that there's something involving an electrified chessboard. I think you can get the solution for how to get through it by retrieving a parrot, which involved putting it in a bag so that you could swim through a section of water without drowning it. At some point, you needed a white robe, and the solution involved putting up a screen in a corridor so that the gelatinous cube would leave the robe behind, and then washing the dingy robe, I think in a washing machine. And the section I remember my brother getting stuck on (and at the time claiming that there was a bug in the game that kept him from getting further) a section involving corridors with automated arrow traps that you had to dodge.
I don't know if it got ported to any other systems. I think the title might have had something to do with light?