Setessan Lasso

Weapon (whip), very rare (requires attunement)

Price: 80,000-160,000 gp | high sentimentality

This lasso looks like an ordinary piece of rope, but when you attack, it glows with golden light and deals a bonus 1d8 radiant damage on hit.

Paid

With the lasso in hand, you can use the lasso to attempt to grapple one creature with advantage and can use a Dexterity (Acrobatics) check instead of Strength (Athletics). When you attempt to grapple foes with the lasso, you have a reach of 10 feet and can grapple foes of any size. You can’t grapple more than one creature at a time with the lasso. You can use an action to place a creature you’re grappling with the lasso under the same effects as the zone of truth spell, and the creature makes its save with disadvantage. If you’re otherwise unable to cast spells, use Wisdom for your spellcasting ability modifier. Creatures can’t cut themselves free from the lasso.

Overpaid

When you attempt to place a creature grappled by the lasso under the same effects as the zone of truth spell, the DC for its saving throw increases by 5.

Source: The Gray Merchant of Asphodel