Direct answer: The Version 2.2 check-in event runs for 14 days after the October 8 maintenance. Each day lets you choose one of two rewards, and completing all 14 days unlocks the rewards you did not choose as a bonus.
How does it work?
- Complete the Main Quest “HP Recovery!” to qualify.
- Log in daily and choose one of two rewards for up to 14 days.
- The event resets daily at 07:00 UTC.
- Rewards cannot be claimed after the event ends.
Official rewards include Hero Pick Up Draw Tickets, Large Cube Key Bundles, Gold, Ingot Selection Chests, Brilliant Engraving Seals, and other progression items.
Official source: Update Celebration Check-In Event.