Polyformic Acid Science

Since it is not yet listed here (and the reason I came here) here is the location of each boss:

Commander Ri'mok: 3rd Boss of the Gate of the Setting Sun
Liu Flameheart: 3rd Boss of the Temple of the Jade Serpent
Gu Cloudstrike: 1st Boss of the Shado-Pan Monastery
Trial of the King: 1st Encounter in Mogu'Shan Palace
Vizier Jin'bak: 1st Boss of the Siege of Niuzao Temple
Yan-Zhu the Uncasked: 3rd Boss of the Stormstout Brewery

The buff is not broken by druid shapeshifts (There is a god!) and all boss kills need to be completed on Heroic difficulty.

When you kill [npc=59613], you can loot an [item=85580]. Click the Polyformic Acid Potion that is on the nearby table and you'll get the disguise [spell=114800] applied to you for one hour (it persists through death). Now, you can use the Empty Vial you looted to "store" your disguise creating a [item=85589]. If you later use this vial, you re-gain the disguise and get replacement Empty Vial. This process effectively gives you 3 uses because each time you store and release the disguise, it becomes less effective (as it becomes [item=85592] and then [item=85593]) and you're eventually left with an Empty Vial and no disguise.

The best way to use this is to get one disguise and store it for later, and then get a fresh disguise by clicking the Potion on the table. This will give you a 60-minute disguise to use in the instance, plus 3 additional uses after you leave the instance with your [item=85589].

Players can use this disguise to achieve Polyformic Acid Science by killing the six listed bosses around Pandaria while under the effects of it. The disguise is available in any dungeon mode (including the normal level 40-ish version for you solo types).

You can store 6 disguise of 1 hour in your bag.

Like said in other comment, there is 3 form of the vial :
- one with 3 use : [item=85589]
- one with 2 use : [item=85592]
- one with 1 use :. [item=85593]
These 3 item have different ID and you can keep one of each dispite that they're unique.

With this in mind, complete 3 solo-run in scholomance non-heroic, and keep all this 3 vial for later use of your achievement without to return back here.

PS: logically,
-- begin to keep the [item=85593] for your first run.
( transform >>> use [item=85580] >>> transform using [item=85589] >>> use [item=85580] >>> transform [item=85592] >use [item=85580] )

-- 2nd run: create [item=85592]
( transform >>> use [item=85580] >>> transform using [item=85589] >>> use [item=85580] )

-- 3rd run: create [item=85589] using [item=85580] just one time.

PPS: As said before already, when you use any form of vial, you get back an [item=85580]

EDIT: the most important thing, when you use your vial for your achievement, take the most empty one. If you don't do this, you will lost a vial.