Crushing Hammer Weapon Mastery

Your pummeling hammer blows leave your foes staggered and ruin their armor. While wielding any flail, hammer, mace, or maul in which you are proficient, you gain these benefits:

• When you hit a creature wearing medium or heavy armor and the attack roll die is odd, the AC bonus provided by the target's armor is reduced by 1 until it is repaired.
• When you hit a creature and the attack roll die is even, it cannot take reactions until the start of your next turn. A creature can ignore this effect with a successful Constitution saving throw. The DC is 8 + your Strength bonus + your proficiency bonus.
• A critical hit applies both effects with no save.
• Inanimate stone and wood objects are vulnerable to the damage of your attacks.