SRD:Fleet of Foot
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You run nimbly, able to turn corners without losing momentum. Prerequisite
Run (PH) , DEX 15, Benefit
When running or charging, you can make a single direction change of 90 degrees or less. You can't use this feat in medium or heavy armor, or if you're carrying a medium or heavier load. If you are charging, you must move in a straight line for 10 feet (2 squares) after the turn to maintain the charge. Normal
Without this feat you can run or charge only in a straight line.