Nice to see another first-person game. Like the mechanic of a grappling hook, but think it needs to be a little more forgiving. Like if your aim is a bit off, it will still auto-aim to grapple onto that block. I think you need to do something at the start to make it clear that those blocks can't be hooked. The problem is that you start facing them and so you assume that you need to grapple with the blocks in front. When you can't you're kinda lost as to what to do until you look around and see the other cube. I would have the grapple something you pick up. So the player needs to explore and find it. I'd also make the grapple change color to match the blocks it can interact with depending upon what switch has been activated. Regardless, an interesting concept that you can definitely build upon for the next game jam.