Entangle (5e Variant Rule)
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Some weapons, particularly those with chains, are designed to wrap around a foes weapon or limbs.
A creature can use an attack with such a weapon to entangle the target's weapon or limbs. The attacker makes an attack roll contested by the target's Strength (Athletics) check or Dexterity (Acrobatics) check. The target has advantage on its ability check if it is larger than the attacking creature, or disadvantage if it is smaller. If the attacker wins the contest, the attack causes no damage or other ill effect, but target becomes entangled by the attacker.
An entangled creature has disadvantage on attack rolls until the attacker ends the entanglement with a bonus action; the attacker drops their weapon or is incapacitated; forced movement causes the attacker and target apart beyond the reach of the weapon; or the target uses its action to escape (as though grappled).
While entangled, neither the attacker nor the target can move apart beyond the reach of the weapon.
While the attacker is entangling the target's weapon, it has advantage on subsequent attempts to disarm the target (see DMG p. 271)
- Player's Handbook