The final boss of Dark Souls 3: The Ringed City is our old pal, Slave Knight Gael.
THE RINGED CITY: FINAL BOSS FIGHT EASY USING RINGED KNIGHT DOUBLE GREATSWORDS! (SLAVE KNIGHT GAEL)
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Slave Knight Gael (Boss), Dark Souls 3 Wiki
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Part Two of the Dark Souls 3 Ringed City DLC Guide (City Proper)
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