Boots of Hermes (5e Equipment)
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Wondrous item, uncommon (requires attunement)
A pair of leather boots, dyed forest green, with small white wings on the sides. If the last thing you do on your turn is moving along the ground, you start your next turn with your movement speed doubled. This lasts until you take an action, receive damage, or are otherwise interrupted, at which point your movement returns to normal.