If you want to gear up a new character or get some quick upgrades, do Dawn of the Infinites on Mythic 0 difficulty. Bosses have around 5-6 million health and drop 493 Champion gear!
When you zone in on Mythic 0 difficulty, make sure to start the instance on Non-Hard Mode difficulty.
In this mode, trash has about 1 million health and bosses have ~5-6 million health, but all the bosses drop item level 493 Champion track gear! At these health pools, it feels like World Quest mobs from last season at these health pools. For geared characters bosses should take less than 1 minute to complete, but nothing seems to really do damage.
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