Second skirmish at the Cave

The Skirmish of the Horcrux Cave took place after Albus Dumbledore tracked down the fake Horcrux to the cave where Tom Riddle murdered some orphans. He and Harry Potter Apparated to the cave, and Dumbledore gave some of his blood to get through. Once inside, they called a boat to get across the Inferi-filled lake. They crossed to a small island. On the island, the locket of Regulus Black lay in a potion that Dumbledore had to drink. While he drank it, he had visions of the duel between him, his brother Aberforth, and the Dark wizard Gellert Grindelwald that led to his sister Ariana's death. When they finally got the locket, Harry attempted to summon water for Dumbledore, but he couldn't. So he got some from the lake. After Dumbledore drank it, the Inferi climbed up from the lake and attampted to kill them. Harry panicked and used every spell or curse, including Sectumsempra, to drag them off, but none worked. Finally, Dumbledore came up and performed their natural enemy - fire. After destroying the Inferi, Harry and Dumbledore went back through the lake and the former Disapparated. When they returned, the Battle of the Astronomy Tower had begun.

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