The Sea’s Legend stands out as being the most cryptic and difficult quest in Pokemon Legends: Arceus. The quest description gives very little away and there are no markers on the map to give you any sort of idea of where you must go.
If you have hit a brick wall with this quest, you are not alone. The solution actually lies in a different Pokemon game. The good news for you is the entire process has been brown down, in detail, below. Follow the steps exactly as this quest requires you to do everything in the exact order and you must do it correctly. Fail a step and you could find yourself unable to complete the quest permanently.
Catch Qwilfish, Buizel & Mantyke
All of these Pokemon can be found in the coastlands, you should have no problem finding these guides. Mantyke can be found closer to the shore near the main camp and Qwilfish can be found further out toward the volcano in the water. As for Buizel, you probably already have one of these having attempted the Big Buizel, Little Buizel quest.
Evolve Qwilfish Into Overqwil
This is the step that many forget, mainly due to many guides from non-gaming websites just copying and pasting guides without knowing the game. You MUST evolve Qwilfish into Overqwil. Evolving requires some additional steps too.
Use the move 20 times with Strong Style
You will need to use the “Strong Style” variation of this move for you to be able to progress to the evolution. It isn’t hard but it takes a bit of time since the PP of the move is 15. You will only get to use it 7 times before running out of PP.
It is best to do this near a camp so you have the chance to rest and restore your PP before trying it again. The fieldlands are the best place as the Pokemon here are incredibly easy to defeat in battle. It will speed up the process for you.
Travel to the Coastlands Camp in Cobalt Coastlands
The coastlands camp is in the southeast corner of the map. You will need to travel here as this is close to the pincer-like rock formation, seen in the image below.
Rest Until Evening
Again, this is a vital step, you MUST rest until evening. Part of the original The Sea’s Legend is that you set sail as the sun is setting. You must wait until the evening to attempt the next step of this quest. You can rest using the tent at the camp and it will fast forward to the evening for you.
Swim Through The Pincer Rock Monument
Now that it is the evening, you will need to run toward the pincer monument and swim through it on the fish.
You must have Buizel, Mantyke and your evolved Overqwil in your party
When you swim through the middle of the pincer rocks, you will see a message appear on the screen, which you can see in the image below.
Head to Seaside Hollow
You may have visited this cave at some stage and wondered what it was for. The mystery is now solved. The cave is part of The Sea’s Legend quest.
You will need to make your way to the seaside hollow and go inside. Before you go in, you need to pay careful attention to the next step as a mistake here can lock you out of ever being able to complete this quest.
Important! Catch Manaphy, do not defeat it
When you enter the Seaside hollow, you will begin a battle with three Phione and one Manaphy. The Manaphy is the critical Pokemon here. It is possible to catch Phione and evolve it to Manaphy but this will take time. The quest requires that you catch a Manaphy. If you defeat it, you won’t be able to complete the quest right away and if you defeat them all, you will never be able to complete The Sea’s Legend.
Once you have captured a Manaphy, you can defeat the others, or capture them too, whatever you wish, it doesn’t matter at this point.
What if you defeat Manaphy?
As soon as you enter the cave, the game will auto save. If you accidentally defeat Manaphy with a strong attack, you can quit the game and reload it. This will bring you back to the entrance of the cave where you can attempt the battle for a second time. This time, you can use a Pokemon that is not as effective and will not defeat it one a single attack.