The Hooked Shortspear can be found in Out of the Abyss, page 224.
This magic weapon grants a +1 bonus to attack and damage rolls made with it. While holding it, you can take a Bonus Action to cause it to shed Bright Light in a 30-foot radius and Dim Light for an additional 30 feet. You can extinguish the light as a Bonus Action.
The weapon has 4 charges. You can take a Reaction immediately after being hit by an attack roll to expend 1 of the weapon's charges and force the attacker to make a DC 15 Constitution saving throw. On a failed save, the attacker has the Blinded condition until the end of its next turn. The weapon regains 1d4 expended charges daily at dawn.
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.