Sling Master

You are a Master of the Sling. You truly understand this simple weapon and use it to its fullest potential. While using a sling you gain the following benefits:  

- All sling ammunitions deal an extra 1 bludgeoning damage.
- Creatures within 5ft from you do not impose disadvantage.
- You may add your proficiency modifier to attack rolls when using the sling as an improvised melee weapon. You may also add your Strength or Dexterity modifier to the attack's damage. The sling must be loaded in order to use it in this manner and your ammunition does not deal additional damage. 
- When you roll a 1 on a damage die you can reroll the die, but you must use the new roll. The attack must be a ranged attack.