Chi-Chi, Hatchling of Chi-Ji

A number of players seem to be having a hard time with Chi-Chi.
With the proper pet setup, Chi-Chi is the easiest of the four celestials.

SNAILS!

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• Chi-Chi only has an elemental attack, which is weak against critters. Snails are critters.
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• Chi-Chi is a flying pet and takes extra magic damage. Snails have a magic attack.
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Whether you have a [npc=64352], [npc=62313], [npc=62246], [npc=63001] or [npc=51635] does not matter, they all have the same abilities.

Maintain the [petability=369] debuff at all times and spam [petability=445].
Use [petability=564] during the third round when Chi-Chi goes [petability=998]. Since Chi-Chi uses that ability on cooldown thereafter, you will not be able to use Dive each time, but each time you use it during her Ethereal, you save yourself about 500 health from the subsequent quills. Definitely do that.

I killed Chi-Chi with two snails, and had an [npc=68819] as a backup in case Chi-Chi needed to be finished, but he did not see combat.

Note that I tried using [petability=310] instead of [petability=369], and got my behind handed to me. It is really important to maintain that debuff.

EDIT: if your two snails can't finish off Chi-Chi (it can happen with some bad rng), use an arcane eye to do the job:
use [petability=475] on the first round, one time is enough to give you the initiative. Use [petability=474] for a free round and either [petability=473] or [petability=483] thereafter. You should not need to use that third ability more than once or twice. [npc=68662] would also be a great "finisher" with [petability=362] and [petability=593]. just don't throw your surge if Chi-Chi's [petability=998] is off cooldown.

The combat rotation I now follow is this:

Round

Ch-Chi

My Pet

1

Tranquility

Pass

2

Fire Quills

Acidic Goo

3

Ethereal

Dive, part 1

4

Fire Quills

Dive, part 2 (quills miss)

5

Fire Quills

Ooze touch

6

Fire Quills

Acidic Goo

7

Ethereal

Swap to Snail #2

8

Fire Quills

Ooze touch

9

Fire Quills

Ooze touch

10

Fire Quills

Ooze touch (dead Chi-Chi)

The fight might last longer if you miss a dive or Chi-Chi decides to pop tranquility in round 10, but you have Dive available at round 11 for his next ethereal and your trusty Darkmoon/Arcane eye if things go south. I haven't seen Chi-Chi pop tranquility a second time in the past few months.

If Chi-Chi somehow destroys your team, switch to the Pandaren Water Spirit/Chrominius nuke strategy. I never had to do that but it's good to have a backup strat.
At this point in time, I'm not sure the howlbomb strat will work that well with the 7.0.3 nerfs. Snails still work, though.

Easily nukeable in four turns with the good old:

Pandaren Water Spirit

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• Geyser
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• Whirlpool
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Chrominius

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• Howl
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• Surge of Power
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combo.

I use Corefire Imp 2/1/2 and 1 snail 1/1/1

Turn 1 Immolation
Turn 2 Wild Magic
Turn 3 Swap to your snail
Turn 4 Acidic Goo
Turn 5 Ooze Touch
Turn 6 Ooze Touch
Turns 7+8 Dive

Easy win :)