Wsp
04-06-2020

I would like to add, KOEI implemented this recipe during an event about 2 months after the CH 3.5 update that boosted Cetus encounter rate for a month. But the recipe seemed to become permanent after that. I hope on Maris we get this once the server updates to CH 3.5 from the get-go

Guilder
05-11-2020

This item's recipe can (eventually) be found at Ibn's Great Lighthouse recipe book in Alexandria upon unlocking the Sea of Wonders -- it will hopefully be a Chapter 3.5 update release.

Required skill/rank: R16 Sewing

Ingredients:
Woollen Fabric x50
Platinum Ore x4
Fish-like Phantom Monster's Relic x5

Note: If you use the Boston Academic Association job-specific skill Tailor's Skills 1 then the required materials are reduced by 10%, potentially saving you a good deal of aggravation in collecting them.Stats:

Durability: 100
Attack: 10
Defense: 15

Navigation +1
Management Technique +1
Evasion +2
EX Effect: Reduce Vigour consumption

This is not (so far as I know) part of any Memorial Album list; it may not be available right away with the launch of Chapter 3.5 either given Wsp's comment.

As to its two variants:

Sea Monster's Boots
Sea Monster's Boots

Those are obtained in a very different fashion. Details may be found on their pages, in time. Cheers.

Source: amuzo.blog19.fc2.com/blog-entry-881.html (recipe), tyojyuhei.web.fc2.com/dol_leg.html (stats)

Guilder
05-21-2020

At the time of Chapter 3.5's release, this item's recipe is not available from Ibn in Alexandria. Looks as if Wsp's warning proved true; let's hope it becomes available on Maris server soon.

Guilder
08-06-2020

As of 3.5 update on Maris, this recipe is now available at Ibn in Alexandria for those who have unlocked the Sea of Wonders.