Original solution still below, but as of a recent patch this has now been fixed as is working as originally intended. Which is get to 50 in any of the main group (The Gold Hoarder, The Voyager..etc..) instead of a single milestone in one of the groups.
Quiet a few requirements had been lower, like sleeping and eating to hit 1 lvl in it, so naturally playing should get this. Of couse you can always check out your own milestones and decide what to go for.
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As of writing this, what should cause this to pop isnt correct. (This may be fixed or stay the same in the future)
All research showed that you needed to get to Pirate Milestone class 50 in one of the ship milestone groups that are listed.
The groups are as follows:
The Gold Hoarder, The Voyager, The Emissary, The Hunter, The Feared, The Rogue, The Ill-Fated,The Captain.
To check this out go to
Ship's Log tab, click on milestones, click on ship milestones
If you click on any one of these groups, you will see a list of ship milestones for those groups.
You have to get to rank 50 in any single milestone within any of these groups.
The one that we (Chevalier, Ztr and myself) worked out/used was the one in The Voyager that lists as Tall Tales Completed.
It will need to say Total 50. / Level 50.
As you are doing this on your own ship and you are a pirate will also get progress for
and pop both achievements at the same time.
What to do:
If you have a second xbox/account, that dummy account needs to have the last checkpoint for the tall tale Shroudbreaker. (This does work for other tall tales, but Art of the Trickster didnt seem to register correctly when we tested
*MCPandaGamerz listed Art of the Trickster worked for him, this may have been fixed, he also listed it seems a quicker turn in than others). See further below for a link how to do Shroudbreaker tall tale.
If you are setting up a session, then your going to have to concentrate on 1 person first as the way captaincy works. If you switch off its becomes a pain.
Not sure if the crew milestone (this is the leveling when you are on someone elses captained ship, but doesnt count towards yours). lvl 50 counts towards the ship item achievement)
You main account you want the achievement on, you will load up your ship/load into game.
I suggest Plunder Outpost, (Kamikisu suggested Galleon's Grave Outpost) or an island that doesn't need to run too far to the mysterious strange in the tavern.
Load your dummy account/partner into ship(ill just use dummy for this).
*Note from Aye of Reach - drop your anchor or sail away andcome back and you dummy/other player will spawn on boat rather than waking up in the tavern each time.
Dummy puts down shroudbreaker final checkpoint down on the table.
Vote.
Main takes the shroudbreaker piece runs towards mysterious stranger in the tavern.
As Main takes the piece, dummy should leave the game. This is important so you dont lose the checkpoint on that account.
Main hands in the shroudbreaker piece to the mysterious stranger.
Wait for tall tale to finished /progress to go up for pirate (and ship if you are doing it efficiently).
Dummy can then come back in,
Rinse and repeat 50 times.
Congratulate yourself with grog and music :)
*Make sure this is all done on the same ship, dont change as a different ship has its own stats/tracking.
xxDamronxx - link for his video showing written above. (Although he states he worked it out... tut tut Damron,couldve named dropped :) )
Shroudbreaker:
If you dont have the checkpoint, its a straightforward easy tall tale.
Here is a link to rarethief guide.
https://rarethief.com/sea-of-thieves-the-shroudbreaker-tall-...xxDamronxx - link for his shroudbreaker video
I finished with Voyager level of 101 for my pirate and ship milestone 50, (i did a lot on someone elses ship, but ended up with something like level 42 in that, by the time we got all 200 items and 30 missions completed.
While you could do this by buying 50 ships not worth it, you'll end up spending approx. 5.3-6million for this DLC so get 15 ships, the cherished trinket, items for your ship, saving items to you custom ship. This also wouldn't count towards ship milestones.