To earn the Shroomtender Shoes, you will need to finish the Necrom Master Angler achievement. This achievement requires you to catch all 12 rare fish within the Apocrypha and Telvanni Peninsula zones.
This is probably going to be the most annoying achievement to complete for a lot of players, as the drop rates for rare fish can be really inconsistent - this achievement could take you a couple of hours or a couple of days depending on RNG.
To make it easier, you can unlock and summon the Sharp-As-Night Companion, as he has a passive Perk that improves your chances to find rare fish when he is with you. Remember that he must be summoned for the Perk to be active, unless you have unlocked all achievements related to Sharp-As-Night and earned his keepsake.
Below are the fish required for this achievement, along with where they can be found and which bait you need to catch them.
Apocrypha Rare Fish
There are three rare fish to catch in Apocrypha. All of the fishing spots in Apocrypha are in Foul waters, meaning you'll need to use either Crawlers or Fish Roe as your bait to catch them. The fish you need are:
- Inkwell Squid
- Quillfish
- Lurker Spawn
Telvanni Peninsula Rare Fish
The remaining nine fish are found in the Telvanni Peninsula.
Three of these fish can be found in Lake waters, so you'll need to use Guts or Minnows as your bait to catch them. These fish are:
- Agarivore Shark
- Deadrock Lobster
- Morrowind Dreugh Shrimp
The next three rare fish are found in Saltwater, so you'll need Worms or Chub as your bait. These fish are:
- Obdurate Albacore
- Puffball Blowfish
- Howling Shark
Finally, there are three river fish that you also need to catch. For these fish, you'll need Insect Parts or Shad as your bait:
- Brown Hat Snail
- Magma Salmon
- Sadrith Splat
Once you've caught all twelve of these fish, you'll earn the achievement and the Shroomtender Shoes.