Repeating Shot Sling

Ammo: sling bullet [5.5e]

Slow (Mastery): If you hit a creature with this weapon and deal damage to it, you can reduce its Speed by 10 feet until the start of your next turn. If the creature is hit more than once by weapons that have this property, the Speed reduction doesn't exceed 10 feet.

This magic weapon grants a +1 bonus to attack and damage rolls made with it when it's used to make a ranged attack, and it ignores the Loading property if it has that property. If the weapon lacks ammunition, it produces its own, automatically creating one piece of magic ammunition when the wielder makes a ranged attack roll with it. The ammunition created by the weapon vanishes the instant after it hits or misses a target.

Ammunition: You can use a weapon that has the Ammunition property to make a ranged attack only if you have ammunition to fire from it. The type of ammunition required is specified with the weapon's range. Each attack expends one piece of Ammunition: Drawing the ammunition is part of the attack (you need a free hand to load a one-handed weapon). After a fight, you can spend 1 minute to recover half the ammunition (round down) you used in the fight; the rest is lost.

Proficiency: simple, sling Source: Eberron: Forge of the Artificer p. 112, Player's Handbook (2024) p. 215