Impact Expert Feat

Prerequisite: Proficiency with mauls or greatclubs
You have mastered heavy blows with bludgeoning weapons. When you hit a creature with a maul or greatclub, you gain a charge of momentum until the end of your current turn. You can expend your momentum charges as a bonus action on one of the following abilities:

• Knock Back (Requires 1 or more charges of momentum): You push a creature within reach of you 5 feet per charge of momentum directly away from you. The distance they are pushed decreases by 5 feet for every size larger than you they are (for example, if you are Medium pushing a Large creature, you need to push them 10 feet to move them 5 feet).

• Take Down (requires 2 charges of momentum): You force a creature within reach of you to make a Strength saving throw or be knocked prone.

• Bonk! (Requires 1 or more charges of momentum): You expend the momentum slamming into a creature within 5 feet of you, dealing 1d4 bludgeoning damage per charge of momentum.

Source: KCLL, page 187

Active Martial Feat Save DC:

• Any time an active martial feat requires a saving throw, the DC is 8 + your Strength or Dexterity modifier (your choice) + your proficiency bonus.