Adventure Time: Pirates of the Enchiridion

As the other solution states, this game is glitchy, and this achievement may not pop upon completion. From researching this in depth, this seems to be a unique problem tied to just the Xbox One version of this title, but no version is free from glitches honestly. This is what I did to try and circumvent it glitching and it seems to work. Thanks to Fireal20 in the comments of the other solution for the foundation of this!

To be on the safe side, when the game tells you to "Return to Ice Kingdom" to confront the Ice King to get more info, that's technically a point of no return. Make sure before you head there that every side quest has been completed as heading there locks you into the final boss with Gumbald unless you dashboard. Failing to do so may bork some of the side quests, mainly the one involving the seven pirate ships. Before fighting Gumbald I was only missing:

Sweet Victory (beating Gumbald)
The achievement for pulling the plug
The four achievements tied to leveling the crew to 10
The "Platinum Trophy" achievement for having every other achievement.

After fighting Gumbald I went directly to pull the plug and did so, skipped the credits, reloaded my save, and went to grind on enemies in the Fire Kingdom. The game explains pulling the plug as ending the game as it will drain the water, it does not. The game will reload in a completed state with the water back to explore. A lot of users here who have saved that achievement for last had the completion one glitch on them.

I didn't run from a single fight in the campaign and went after most chests guarded by enemies and after Gumbald only BMO was level 9. The grind for everyone in the fire Kingdom took me an extra half hour after pulling the plug, and I tried to pace the bonuses in a way that wouldn't pop two leveling achievements in the same fight. This one popped before I got the Hero Finn achievement.

TLDR:
Do everything side quest related and miscellaneous achievements (Lighting the fires, finding the snail etc) before returning to see the Ice King.
Fight Gumbald there.
Go directly to pull the plug after.
Skip credits, continue back into the world, head to Fire Kingdom to grind for XP to become level 10 with everyone.


In this order, your chances of it unlocking seem to be higher than by pulling the plug last. Good luck and let me know if this worked for you. At the time of posting a patch is APPARENTLY still in the works, but I wouldn't hold my breath.

UPDATE: This is not a be all end all guide, moreso how I managed to get the achievement to pop. Your mileage may vary!

With the April 12 2019 update, this achievement has been fixed. You may play the game normally and only worry about pulling the plug last. The order of the other achievements doesn't matter anymore.

If you have finished the game already, try applying the patch and loading up the main menu. I saw several reports of people getting the achievement that way.

Hi guys, I went for all the achievements of this game and, of course, the last one (Pirates of the Enchiridion) didn't pop up.

I was able to fix it and the solution was quite simple. So, I'm writing it here to try to help someone facing the same problem:

1) I've closed the game (from x1 dashboard)
2) Logged out my account
3) Logged in my account again
4) Opened the game
5) Chose the option continue (to load the game with all other achievements)
6) After loaded my game the achievement popped up!

Hope these steps can help someone.

Cheers

I don't know if this will help or not but I made sure to max all of the powers of the adventure crew. I mean even after hitting level 10 with everyone I made sure all their stats were 10 as well before going against the last boss. All the other achievements were done except for the boss and pull the plug. I don't know if I was just lucky or not but apparently I got the achievement at first it didn't show up but I checked on here it said I got it. The game last night still shows it unmarked while xbox.com shows it being achieved so take it as you will.
Your results may vary

** Disclaimer: Not a guarantee, this is just what I did and for some reason it worked **
Just wanted to share what I did to get this to pop.

Tried to read up on all the possible ways to get this to work.

Here's what I did:

Finish all side quests.
Head to Ice kingdom with all characters level 9.
Beat uncle gumdrop.
BMO levelled up.
Went back to fire kingdom to grind the other 3 characters to level 10.
Pulled the plug.

Both the Plug and Final Achievement unlocked right after one another.
Cheers