Could I have some impressions of this magic sash/grapple hook?

Really weak, definitely not rare. This is the sort of thing that barely qualifies as a magic item

Range is very short.

The first use requires a successful attack roll and a successful athletics check, so you basically have disadvantage whenever you use it. Compare to the cantrips lightning lure and thorn whip, or just grappling someone and dragging them where you want to go, various battlemaster manoeuvres that move people about, all of these options are better than the item. The ranged attack roll requires dex, and the athletics check requires strength, so very few characters will be able to use this effectively at all.

The second benefit is also pretty situational, it’s weird that the AC is the same regardless of the material and any “handholds”. Most of the time you could just climb, fly or walk where you need to go.

/r/dndnext Thread