Nightmare Dungeons (NMDs) are sigil-keyed instanced versions of the campaign's regular dungeons, repurposed as Diablo IV's Glyph leveling engine. Tiers run 1-100, monster levels scale from 54 (T1) to 154 (T100). Sigils roll one positive player affix and two to four negative affixes that punish your build. Every NMD clear levels your equipped Glyph — NMDs are not the raw XP king anymore (Pit and Hordes beat them) but they remain the only way to level Glyphs.

Sigils

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  Drop sources Any endgame activity — Helltides, NMDs themselves, Whispers, Pit, Hordes.
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  Crafting Occultist can craft/upgrade/salvage Sigils using Sigil Powder from salvaged lower-tier Sigils.
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  Affixes 1 positive player affix + 2-4 negative affixes per Sigil. Watch for Resource Burn and Drifting Shade — the most punishing.
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  Revive cap Tier 21+ caps revives at 4. Die a fifth time = dungeon fails.

Run Pattern

1. 1 Clear event objectives (usually "kill X monsters" or "collect X items")
2. 2 Find and slay the Bane of the Dungeon (named monster marked on your map)
3. 3 Kill the dungeon boss in the final arena
4. 4 Open the Glyph Altar after the boss — this grants Glyph XP to your equipped Glyph

Rewards per Run

• ◆ 4 guaranteed items including at least 1 Legendary / Unique
• ◆ Whisper Cache credit (Grim Favors count toward weekly cache)
• ◆ Crafting materials based on tier
• ◆ Glyph XP at the altar — the main reason to run NMDs at endgame
• ◆ Higher tiers = higher item level drops + more Glyph XP