Season 6 launched alongside Vessel of Hatred — D4's first expansion. Spiritborn, Nahantu, Mercenaries, the Kurast Undercity, and the Torment difficulty system all debuted. The class imbalance was severe enough to dominate discourse the entire season: Spiritborn crushed everything, and Blizzard chose to buff other classes rather than nerf the new one.

Vessel of Hatred Content

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  Spiritborn class Jungle warrior channeling 4 Spirit Guardians (Jaguar, Eagle, Gorilla, Centipede). Vigor resource that does not regen.
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  Nahantu region Torajan jungle. Kurast Bazaar + Docks return from D2.
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  Mercenaries Raheir, Subo, Varyana, Aldkin — companion NPCs with their own skill trees.
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  Kurast Undercity 3-floor target-farming dungeon with Tributes + Attunement.
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  Dark Citadel Coop-only raid-style endgame.
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  Torment system Replaced World Tiers — 4 leveling tiers + 4 Torment tiers = 8 total.
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  Runewords D2 legacy system returns. Ritual + Invocation rune pairs.
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  Paragon 300 Cap moved from 200 to 300.

Seasonal Mechanic — Realmwalkers

Massive demonic constructs spawning every 15 minutes rotating through the 5 base-game regions. Defeating one opened a portal to a Seething Realm (mini-dungeon) ending at a Realm Gate boss. Seething Opal consumables (Torment, Socketing, Aether, Equipment) buffed drops. Realmwalkers filled the traditional "seasonal boss" role.

Top Meta Builds

• ◆ Evade Spiritborn (S+ tier, banned in many group contexts)
• ◆ Quill Volley / Gambitborn Spiritborn
• ◆ Touch of Death / Deathborn Spiritborn
• ◆ Heartseeker Rogue (best non-Spiritborn)
• ◆ Lightning Spear Sorcerer
• ◆ Cataclysm Druid
• ◆ Blood Wave Necromancer
• ◆ Double Swing Barbarian