This dungeon can only be cleared once during the event it appears. You can get one of the Spirit Jewels.
After clearing it once, the dungeon will disappear. You can pick the Spirit Jewel you want by quitting out of the dungeon (but it will take 50 stamina each time).
Note that just because this is a gift dungeon, doesn't mean you can take it lightly. The enemies are at the same difficulty as their Legend-rank invade versions.
Challenge of a LifetimeEdit
||2400 (48 / Sta)
||1814 (36 / Sta)