Blunt Weapon Master

You’re a master of blunt weaponry and know exactly where to land heavy blows. The following benefits apply only to the club, greatclub, mace, flail, maul, and warhammer.

• When you damage a creature with any of the listed weapons, their speed is reduced by 5 feet until they regain hit points. The effect of this feature is not cumulative with itself. 
• When you roll damage for any of the listed weapons, you deal an additional 1 damage if a damage die shows maximum result.
• If a damage die of any of the listed weapons shows a result of 1, you can instead treat the result as the maximum of the die. You can use this feature 3 times and you regain all expended uses when you complete a long rest. You must choose to use this feature before the DM announces the result of the damage.