I beat Mistlands with fully upgraded padded helm / leggings and root chest piece for the pierce resistance. Only made the giant crossbow, giant iron sledge war hammer and the dead raiser because I had 2 green skulls. Didn't bother wasting time on any of the other items and mostly enjoyed making a base in the plains outside mistlands using marble and stone.

The mist mechanic sucks. The terrain sucks. Finding dungeons sucks. Finding Dverger Forts is easy but getting reliable certain drops from them that are required for progression is rng which kinda sucks. The monsters are meh when it comes to balance. Frostner, Iron Sledge and Drauger Bow pulled me through Mistlands with little difficulty - mostly died from upsetting the Dvergers and maybe once to the flying butt.

I felt like the game was cheesing me with the artificial difficulty increase when it pertains to the mist and terrain making exploration more of an annoyance then exciting or intriguing so I eventually stopped looking for dungeons / magical flesh blobs and just cheesed the boss using the Mistland's version of iron sledge weapon (good job developers on that arena design lol).

I think the best thing that Mistlands offers is the new building material pretty much because the environmental design just undercuts any amount of enjoyment I can find in a biome that was just released.

Here is my base after killing discount Duriel
https://steamcommunity.com/sharedfiles/filedetails/?id=2902746991