Striker Feat

You move like the wind, striking faster than your foes can see. You gain the following benefits:

Prerequisite: 4th level

• Ability Score Increase. Increase your Strength, Dexterity or Constitution modifier by 1, to a maximum of 20.
• Battlefild Dancer. Each time you hit a creature, your movement speed increases by 5 feet until the end of your turn. If you attack and hit a creature with a melee weapon attack, you can pass through it space treating it as difficult terrain.
• Gain the Slashing Dash special attack (below).

Slashing Dash - Active Ability (Attack)

• When you take the attack action on your turn, you can replace one of your attacks with a rapid burst of movement, moving up to 30 feet along any surface in a straight line.
• You can move on vertical or horizontal surfaces with this movement, can pass through creatures, and do not provoke attacks of opportunity, but cannot pass through objects or terrain. If you are carrying a weapon you are proficient with when ou take this action, each time you pass through a creature, it must make a Dexterity saving throw. A creature takes 2d6 + your Strength or Dexterity modifier (our choice) damage of your weapon type on a failed save, or half as much on a successful save. The number of d6 increases by one when your proficieny bonus increases (with the total number of d6 equaling your proficieny bonus). 

Once you use this feature you cannot use it again until you complete a short or long rest.
Source: KCLL, page 185

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.