You can repeatedly close the distance when foes try to move away, without impeding your normal movement.
When using the Step Up feat to follow an adjacent foe, you may move up to 10 feet. You may still take a 5-foot step during your next turn, and any movement you make using this feat does not subtract any distance from your movement during your next turn.
You can only take a 5-foot step to follow an opponent using Step Up.
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SECTION 15