ShadowQuilava

ok so i have now completed Episode 15 of Reborn, now there is Rejuvination to deal with, Garatina, level 63 how do i deal with such a monster? i dont have a single pokemon that can learn Destiny Bond so im stuck there, if someone can tell me where to find a Reaper Cloth so i can evolve Duskclops that would be great, or at least a Item Location thing