Roc's Feather (5e Equipment)
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Wondrous item, uncommon
This magically enhanced feather is said to originate from a benevolent kargaroc or helmaroc. While you clutch it in your fist, you feel unusually light on your feet. The distance of your long jump and your high jump both increase by 5 feet, regardless of whether or not you have a running start. You also have advantage on any Strength (Athletics) or Dexterity (Acrobatics) check which focuses on jumping, such as quickly leaping between platforms.
You only gain the benefit of roc's feather while you clutch it tightly in your fist, and are not holding anything else in that hand.