Cookie's Leftovers

Cookies Leftovers is the final fight of the 7.2.5 Deadmines pet battle dungeon. This magic pet is quite tough with strong magic attacks, which simply asks for a:

• 
  
• Mechanical Pandaren Dragonling (1 2 2)
• 
  
• Teroclaw Hatchling (2 2 2)
• 
  

Decoy
Thunderbolt
Then Thunderbolt and Decoy on cooldown and otherwise use Breath

Usually the Dragonling manages on its own, but if you need your Teroclaw, Dodge + Alpha Strike takes care of that.

For all the other fights, here's Xu-Fu's full Deadmines challenge mode guide.
Enjoy and good luck in the dungeon!

Killed it in 6 rounds.

Vale Flitter (Call Lightning)
Unborn Val'kyr (Haunt)
Zandalari Anklerender (P/S)(Hunting Party, Black Claw)

Round 1: Call Lightning. Vale Flitter gets put to sleep.
Round 2: Switch to Val'kyr.
Round 3: Haunt. Switch to Anklerender.
Round 4: Black Claw.
Round 5+6: Hunting Party.

Soloed with Mechanical Pandaren Dragonling

Just Decoy and Breath.