The following actions are available.
With a garrote (a strong cord or similar device) you can make a special attack against an unaware or incapacitated target. Your target must be no more than one size larger than you. You automatically grapple your target, but you must succeed on an attack roll against a target that isn’t incapacitated. While you maintain this grapple, you can’t use your hands for another action.
At the end of each of your target’s turn, your target suffocates as you choke it. If it suffocates for a number of consecutive rounds equal to 1d4 + its Constitution modifier (minimum of 1 round), it is reduced to 0 hit points. If you continue to strangle an unconscious target, it automatically fails its death saving throw as if hit by a melee weapon attack at the end of its turn. If a creature doesn’t breathe, it is grappled normally.
The first time a target breaks your grapple it can breathe normally, but is still grappled by you until the end of your next turn. During your next turn, you can attempt to strangle your target again by succeeding on a grapple check. If the grapple check fails, your target is no longer grappled at the end of your turn.
A garrote can be cut, has AC 10, 5 hit points, and immunity to bludgeoning, cold, necrotic, poison, psychic, and thunder damage. When cut this way, your target is no longer grappled, and your garrote may be rendered unusable depending on its length.