STAGE 1
Right next to the hydra outpost in buccaneer beach type /listen 10 times (some heroes don't have this emote), don't be in a party.

STAGE 2
Go around buccaneer beach destroying everything and in time you will get an achievement "message in a bottle"

STAGE 3,

Each map fragment takes about 10-30 minutes to get, just keep killing mobs.

• Pirates Treasure Map, Fragment 1,
  
  Darkness = defeat hand ninjas anywhere in game
  
  
• Pirates Treasure Map, Fragment 2,
  
  Undertow = Thugs in hoods hideout (better chance in story mode)
  
  
• Pirates Treasure Map, Fragment 3,
  
  Boreal = kill things in norway
  
  
• Pirates Treasure Map, Fragment 4,
  
  Meteor = vibranium mines one-shot (better chance inside mines)
  
  
• Pirates Treasure Map, Fragment 5,
  
  Volcano = Mutate Marsh

Upon completion of fragment 5, you will get the "buried treasure" achievement and a purple pirate Deadpool team up achievement chest will be in your inventory, when u right click on it the Deadpool team up it will be DROPPED ON THE GROUND!!!

make sure you pick it up.