The Cloudy Mountain one is more like classic Intellivision stuff. I think that one was well-received at the time, but I actually don't often hear much chatter about Treasure of Tarmin. Tarmin being a first-person dungeon crawler gives it some legs since it's an inherently "classic" style, although calling the graphics and controls dated would be a huge understatement.

Players are absolutely going to need the game manual, and even then some item use cases will have to be figured out.