Deadmines: Sea'in Red

This quest was added in patch 7.1, and unlocks the [transmog-set=889] set. To obtain it:

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• You're going to need a Rogue in Outlaw specialization. You don't need to be level 110.
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• Enter [zone=1581] Normal
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• Reach Ironclad Cove, the area with the wooden catwalk and the big boat (near the last two bosses)
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• Optional: if you don't have a [npc=7387] keep killing [npc=48522] until you get a [item=8492] with one inside
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• Locate the [npc=115839], found at these coordinates
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• Summon your [npc=7387] and stand close to the [npc=115839], an extra button with a [spell=230148] will appear. If you click it you'll climb the wall
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• Accept the quest Deadmines: Sea'in Red from [npc=115818]. He's gonna ask you to obtain 100 Blodied Defias Bandanas from the enemies inside the instance. If you already killed them all just reset the instance to complete it (remember that you need to do it in normal difficulty)
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• Turn in the quest and enjoy your [transmog-set=889] set!
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Credits: Reddit users /u/LunaeLux, /u/Kaeligos, Wowhead user Sutcliff and many others who helped discover it.

I haven't seen this mentioned anywhere yet. If you return to the ghostly parrot to head back up and turn in but the extra action button doesn't appear, just dismiss your Green Wing Macaw and re summon it. I hit that issue and that caused the button to show up so I could finish.

Okay, there's a short guide:
Some thing you need to know before:

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• First, [item=142273] can be obtained by only Rogue, Outlaw spec
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• You dont have to be 110 level to be able to pick up the quest Deadmines: Sea'in Red
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• There are five items in set: [item=10399], [item=10400], [item=10401], [item=10403] and [item=10402]
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• You dont have to be rogue only to transmog the set, other leather wearers are ok too
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Fine, now the guide:

1. 
   
2. Go to [zone=1581] instance, entrance located in Westfall at 25.4 51.0 point (there's long way through the underground
   There's also video if cant find: https://www.youtube.com/watch?v=H3zrzcoHqj0
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4. Run normal and proceed till you found a giant cave with ship inside it (Ironclad Cove). Also, skip all mobs, slay only bosses to open doors
5. 
   
6. When you come into Ironclad Cove, turn left, there you'll see a ghostly parrot far away, above a corpse next to a water
7. 
   
8. Come close and summon battle pet, [npc=7387]. You can obtain it at AH or killing pirates on the ship, [item=8492]. When you summon the pet, there an extra button will appear, [spell=230148]. Use it to reach a hidden place, where [npc=115818] is
9. 
   
10. Pick up Deadmines: Sea'in Red quest. [item=142349]s have 100% drop chance from each mob (including monkeys and parrots, lol). There are enough mobs in instance to get all 100 within a single run reset (if you skipped them, ofc)
11. 
    
12. Get back to [npc=115818] and turn in the quest, use [item=142273] to get full set. Visit transmogrificator to see what you've got
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Deadmines: Sea'in Red videoguide, https://www.youtube.com/watch?v=pz75NeKxoyI