THE PIT TIER GATES MASTERWORKING
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Masterworking materials drop by Pit tier, and masterworking is what takes a finished build to the top of its range. That makes a Pit push upstream of almost everything else here: it is not a leaderboard, it is the thing that decides how good your gear is allowed to get.
Nightmare dungeons level glyphs. The Pit drops masterworking materials. Infernal Hordes pay out in Burning Aether for gear and gold. Kurast Undercity trades a timed run for targeted loot. Helltide is the general-purpose farm. Picking by what you need rather than by what sounds hardest is usually the cheaper order.