Dragonkin Battler of Northrend

For this one, Kalimdor and Northrend i only used 3 pets:

Nexus Whelpling (1,2,2)
Stormborne Whelpling (1,2,2)
Stormie (1,2,2)

I always started with Arcane Storm and made sure i kept it up whenever i could
Then i just spammed Mana Surge between the cooldown.

Switch between the pets to always hit enemy with Mana Surge.

You can of course use Tail Sweep to finish the pet if its Low. Thats up to you.

NB! Always make sure your pets have full health and all 3 are alive before entering battle or you wont get credit towards the achivement.

Happy battling!

Nearly Headless Jacob is a bit of a pain versus Dragonkin.

His first pet wants to DoT you and swap you to the backline to rot. To counter this, I used my Bronze Whelpling (needs 290 speed or higher) to stun "Spooky Strangler" and it will usually get swapped out. Bronze whelpling also has Lift-Off which I used to avoid the Call Darkness from "Stitch" (its usually its first cast). So right off the bat you avoid a massive amount of damage.

My second pet was a Nexus Whelpling for the Arcane Winds and Mana Surge combo for a lot of damage.

My final pet was a Dream Whelpling with Emerald Bite, Emerald Presence, and Emerald Dream. I would keep up Emerald Presence and then try to cast Emerald Dream to stop Spooky Strangler from swapping my Dream Whelpling. It usually will cast Doom, Agony, then try to swap you. So as long as you're dreaming before the swap, you should be good.

This worked for me with some RNG (Nearly Headless Jacob posed the most trouble), but a little messing around with the order of the pets and swapping Nexus Whelpling to 1/2/1 for Wild Magic buff did the trick after a couple of tries.