Mythic: Raszageth the Storm-Eater

I can confirm that as of today, 10.2.6 (DF Season 3), Deep Cuts From the Vault is still achievable by defeating Mythic Razzy, thereby earning Mythic: Raszageth the Storm-Eater.
The [item=202047] will appear in your bags, and once you use it, it unlocks the Mythic/Elite_PVP visual effects for all recolors of all tier sets across your account once you've collected the base appearances (along with Mythic/Elite_PVP recolors sans effects, if you need that for a more muted transmog). Remember that the [Revival Catalyst] has infinite charges for DF Season 1 & 2 tier items, meaning if you get eligible gear at the right iLv, you can earn these appearances more quickly.

I completed this achievement today with a pug after a few false starts and time spent prog'ing each phase so people could learn what to do. With a little patience and a decent group, it's not so bad. Unfortunately, I've tried to pug this fight with multiple other groups this season with most of them failing to reach P3, but with some luck, I was finally able to mark this achievement off my to-do list.

PRO-TIPS:

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• The armor appearances may not appear until you completely log out of the game client (I had to take it a step further by closing the BattleNet app as well).
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• When searching for your new appearances, remember to have "Not Collected" chosen in the filter menu, and search for the exact primary item name (not the secondary shared-appearance name; using the raid name or boss name also doesn't show these special versions, only the base items).
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• For example: On my mage, if I search the shoulders tab for [Ascended Squallspires], [Dathea], or [Vault of the Incarnates], I see just the original four difficulty recolors. However, if I search for [Crystal Scholar's Beacons], I see ten results: the four vanilla recolors alongside six other versions (LFR, Normal, Heroic, & Gladiator_PVP with effects; Mythic & Elite_PVP without effects).
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