The Hooked Shortspear can be found in Out of the Abyss, page 224.
When you damage a creature with an attack using this magic weapon, the target can't regain hit points until the start of your next turn.
On a hit with this weapon, the wielder can forgo dealing damage and attempt to trip the target, in which case the target must succeed on a Strength saving throw or fall prone. The DC is 8 + the wielder's Strength modifier + the wielder's proficiency bonus.
A light weapon is small and easy to handle, making it ideal for use when fighting with two weapons.