when you first unlock the frozen highlands and the fortress, you can enter the prime enchanters dungeon even though there are bars over the dungeon door and it shouldn’t let you inside. i did this after the igloo quest to save those villagers, but i think you can do it as soon as the fortress is unlocked.
it will let you inside the dungeon, but the buttons for the bridge wont work, and the prime enchanter will not spawn. activating the proper quest and then running the dungeon will cause the traps to not work, and after defeating the boss the respawn side quest marker will not show up on the world map, but the respawn statue will work.
all of these sub issues would be prevented if the door was properly locked before you were supposed to access it.
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