Structures
+ progression path

These aren't sorted by difficulty. ONLY listing the custom structures important for advancements, gear, enchants, quests...
Please try to explore most of them before not doing so because of the loot. The term "Useful junk" means many things. It can mean both wind charges, golden carrots... so on, but also common armor trims, building blocks, vines.... There's no "one-word" term to use for it.


Progression path

You start by getting full protection IV netherite armor. Then you can move on to getting the Asflors sword, by finding and exploring the Asflors village and finding the necessary books to guide you on the way to the main loot.

After getting the sword, you can test your strenght in the Alfheim tree. If you trust yourself that you can loot it with ease, go to the runic labyrinth, featuring many more mobs and two more items to get: The Twillight of Yggdrasil bow and the Elven Bow.

When you get those, you move on to the overworld, now you need to get spiteful 3 on your sword and probably traveler 3 on your boots, you need to explore to find those, they're not 100% guaranteed anywhere.
Then you explore and find the Echoing forge, where you get the Gea's gift II enchantment. Get a full set with it.

While within the Echoing forge, you might get protection V pants from the forge's pale part chests. You can skip this step, but it's safer to have a larger protection than not.

Now it's time for the hard part, going to loot Asgard, where you can get Gungnir, but you can also get your gear lost very easily, proceed with caution. You can also get Nugrak's bite and Zyask's strike within the structure.