The Grappling Hook (GH) would be a tool the player can find along the path of the future main quest, akin to the climbing gear, similarly assisting them with climbing harsh cliffs. It functions as an addon of the previously obtained climbing gear.
Function
The GH can only be used outside of combat. When used, the hook quickly shoots out in a straight line before descending (akin to cannonballs in this game) and will hook onto any climbable surface. Think of it working similarly to the Hookshot in most Zelda games, with the user shooting to the location of the hook.
(Requires Climbing Gear) If the user is followed by NPC crewmates, if close enough, those crewmates will be attached to the user by a rope, and travel with them.
When hooked onto a wall, the player will fly over to the hook’s location and begin climbing the wall.
When hooked onto a ceiling of a climbable material (and yes I know you normally can’t climb ceilings), the player will shoot over to the hook’s location and hang from it, slowly losing stamina. While hanging from the ceiling, the player is unable to attack, and will fall if struck. If not already consumed, the player can dodge-reflex from the GH without needing to unequip the tool.
When hooked onto the floor, the player will fly over to the hook, and simply stand when they arrive at the hook’s location.
Specific Details
The GH can be used mid-air, briefly suspending the user in the air akin to spells. However, it will consume an Air Movement if used this way.
The GH can be unequipped mid-grapple, and the user will begin to fall.
If the user is struck while the GH cable extends outward, its usage will be cancelled.
If the GH makes contact with an unclimbable object, entity, or surface, the hook will quickly retract back to the user.
Upgrades
Similar to pouches, the player can find pieces of GH cable scattered around the world. Finding these counts as an exploration task.
With each piece of cable obtained, the maximum distance the hook can travel and the speed at which it travels is increased.
Closing Notes
I appreciate climbing gear being added to the game, and it’s cool that you can bring your crew with you up large cliffs to explore with them, but the ability to hook onto walls with it left something to be desired. It’s intended function (at least I think) is mainly meant to save you from a long fall, though my imagination thought it’d work like a proper grappling hook, which is why I made this suggestion.
Having more ways to traverse rough terrain, especially vertical rough terrain, is something the playerbase is going to need, especially with the exclusive content planned for the Dark Sea, and you know how rough the geography can be in there. Also grappling hooks are fun in any game.