With the first Beta build, Blizzard has updated some Delve achievements to be explicitly tied to Season 1, meaning players cannot obtain them once Season 2 starts.
Note that they also removed the rewards from these achievements, so they might be moved to different sources in the future or removed completely.
- Defeat Zekvir in his lair on Tier ?? before the release of the next season of delves.
Reward removed: Title: Ascension Breaker - Defeat Zekvir in his lair on Tier ?? without any other players in your party, before the release of the next season of delves.
Reward removed: Airship Customization: Void - Defeat Zekvir in his lair before the release of the next season of delves.
Reward removed: Cosmetic: Zekvir's Spine
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