Any new piece of gear that drops at 441 or higher can be upgraded to Item Level 447 on the Patch 10.1.5 PTR using the new 'Myth' upgrade track including Mythic Raid, Mythic+ and Very Rare Heroic pieces.
Mythic RaidIn Patch 10.1, Mythic raid items, especially off the first few bosses, have very small value and it seems like Blizzard may be trying to address this. A new Myth track has been added seemingly for Mythic Raid items only which allows players to upgrade these items to 447 Item Level using Aspect's Shadowflame Crest. This should make early Mythic bosses much more valuable! This means that the following bosses will now drop items that can be upgraded to 447:
Kazzara: 441 Myth (1/3) Amalgamation: 441 Myth (1/3) Assault: 441 Myth (1/3) Forgotten Experiments: 444 Myth (2/3) Rashok: 444 Myth (2/3)Anything from Zskarn onwards already drops at 447 and is already Myth 3/3.
Mythic+Mythic+ vault gear that drops at 441 item level or higher (Great Vault 16 — 20) seems to also land on the Myth track. This should make keystones 16- 19 much less 'dead' as Great Vault loot from these ranges can be upgraded to the max of 447!
Heroic RaidAs Very Rare loot drops +7 item levels higher, this means that the Class Trinkets (Neltharion's Call to Chaos, Neltharion's Call to Dominance, Neltharion's Call to Suffering) from Neltharion and Voice of the Silent Star from Sarkareth are on the Myth track as well!
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