Edge RunnerSource Heroes of the Streets pg. 28
You move with speed and assurance in places that cause others to fall into danger.
Prerequisites: Dex 13.
Benefit: You can move at full speed while using Acrobatics to balance on narrow surfaces, and do not become flat-footed or lose your Dexterity bonus to AC while doing so. You also gain a +4 bonus on Climb checks to catch yourself while falling. You also gain a +4 bonus on saving throws against effects that would cause you to fall into a pit (such as create pit or a pit trap). This bonus does not apply to your CMD against bull rush or trip attacks.