Exocave is a first-person shooter about exploring a subterranean world. One of the most important parts of the game is movement, which should feel natural and allow players to traverse chasms and other obstacles in the depths.
For world generation, I recently implemented horizontal cavern systems and vertical chasms connecting them. However, with only jumping and limited wall climbing, there was no way to easily move around in the new terrain. So the obvious solution was adding a grappling hook.
You can fire it at any surface and it will reel you toward it. You can jump off or fire again at any point. For the sake of prototyping, you start with the grappling hook item, but eventually it will take efforts to obtain it in the game.