Savant's Slipknot

 is a Cypher in Torment: Tides of Numenera.

Description
At first glance, this appears to be a crude arm bracelet woven in the shape of a hangman's noose, the kind of item a macabre child might make. Closer examination of any of the three cords used in the weave twists the perception of the viewer, making that cord appear to grow thicker while one of the other two thins and fades from sight. By breaking the knot, it is possible to absorb the object's powers.

Location

 * Valley of Dead Heroes: Fished out of the acid pool.