For Pride's Sake, the River of Stars - S2.E40

After Lucy calls multiple spirits in a row to fight Byro her magic is quickly drained, though Virgo gives Lucy a Spirit World whip that can extend and contract to help in the fight. When Byro is defeated by the timely arrival of Natsu, Coco gives the key to Lucy, but it is stolen by Sugarboy, forcing Gray to pursue him.