The Sealed Treasury lag issue in Where Winds Meet appears to be tied to the quest segment where you chase Blackclad through the Imperial Palace content, and several recent guides/posts indicate players were running into loading or progression hiccups around that step. The content itself is part of the new Imperial Palace expansion and the Sealed Treasury campaign, which launched on May 28, 2026 UTC.

What the issue seems to be

Recent community posts and walkthroughs point to two related problems: the Sealed Treasury quest not loading smoothly for some players, and the chase segment with Blackclad causing lag or stutter during progression. The quest guide shows that Blackclad appears after the puzzle sequence and pursuit section, which makes that chase the most likely spot where performance issues would show up.

Why it may happen

A few plausible reasons fit the reports:

  • The new area is heavy on NPCs, scripted movement, and quest events, which can make loading more demanding.
  • The chase sequence is tightly scripted, so any asset delay can feel like a quest hang or lag spike.
  • Some players report the quest simply not loading properly, which suggests a quest-state or streaming issue rather than just combat performance.

Practical fixes

Based on the available guides and player reports, the safest things to try are:

  1. Reload the area or restart the game if the quest stalls.
  1. Make sure you already completed the required main-story step, since the quest unlocks only after Throne and Tempest 1.
  1. Re-read the in-game mailbox letter and return to the Sealed Treasury at the correct time, since the quest trigger depends on that setup.
  1. If the lag happens only during the Blackclad chase, lower graphics settings temporarily and retry the sequence after re-entering the area.
  1. If the objective breaks, backtrack to the previous checkpoint and let the scripted chase restart cleanly.

Community context

The discussion around this quest is very recent, with the Sealed Treasury campaign rolling out alongside the Imperial Palace expansion and attracting guides, boss-fight clips, and “how to fix loading issues” posts within days of release. That timing suggests the problem is more likely a launch-week quest/streaming bug than a long-standing gameplay mechanic.

Bottom line

If your “horse chase black clad” problem is the Sealed Treasury pursuit, the most likely fix is a reload/restart plus re-triggering the quest from the correct checkpoint, because the issue seems tied to loading and scripted chase progression rather than a unique boss mechanic.