This completely slipped my mind for some reason when making Ariala. Anyway, I've searched the Library, and there's no mention of a grappling hook anywhere, I don't believe. There's hookshots and clawshots and switch hooks...but no grappling hook. I know, I know, there's a million variations of the thing, so why add the grappling hook? Well...uh, unlike the other items, the grappling hook actually has cultural significance to the Rito as a race. All Rito should be allowed to start with a grappling hook for free, as they're the most important tool that the Rito are given in order to complete the trial for their wings. So, yeah...unless I'm just blind, they should be added. And then Ariala should totally have one.
SM is right. A grappling hook is considered common-tier. As such, it can be freely acquired and is not included in the library as a treasure. It shares this trait with bows, slingshots, mundane shields, mundane weapons, and several other canonical items. ...However, in some of its canonical appearances, Link can use it to deftly pry objects from a foe's pockets at a distance. Link's apparent ability to do that in of itself is superhuman, so arguably the ability to use a grappling hook so deftly should be a skill earned as a treasure. Perhaps it should be added to the Library..?
Yeah, I totally see all of your points. I like the idea of grappling abilities. So is it safe to add a Grappling Hook to my inventory without anyone yelling at me?
Yes, it is. I'm planning to add a bunch of new treasures to the library soon, so I'll be sure to include a grappling ability or two.
