Stardust

It really did work on the first try!

Unborn Val'kyr + Pygmy Direhorn + Son of Sethe

UV: Curse of Doom, Haunt, "dies"

PD: Trihorn Shield, Stampede, dies

UV: Shadow Shock, dies

SS: Touch of the Animus (on cooldown), Drain Blood (on cooldown), Plagued Blood (filler), dies with Apocalpyse, resurrects!

After losing a couple pet battles, tried this strategy and won immediately (gratitude and credit to Bucck on Wowhead):

Unborn Val'kyr + Pygmy Direhorn + Son of Sethe

UV: Curse of Doom, Haunt, "dies"

PD: Trihorn Shield, Stampede, dies

UV: Shadow Shock, dies

SS: Touch of the Animus (on cooldown), Drain Blood (on cooldown), Plagued Blood (filler), dies with Apocalpyse, resurrects!

Suck it, Algalon!

Very good and quite underrated pet. With its Moon Tears into Celestial Blessing, she can make really good combo team with Xu-Fu, Cub of Xuen, Ban-Fu, Cub of Ban-Lu, Trunks and/or any pet with Creeping Fungus or Spirit Claws. Also beautifully designed and awesomely cool looking ;).

I tried EVERY single combo recommended on here, wowhead and wow-petguide.  What FINALLY worked for me was Zandalari Anklerenderer 2/2/2, Emerald Proto-Whelp 1/1/2 and Mechanical Pandaren Dragonling 1/1/2.  I don't know if breeds matter or not but I think probably a P/P would be best for the anklerenderer, I used S/S and it never lived to finish off the first pet.  This team is HIGHLY dependant on RNG so just don't give up.  It took me about 50ish tries (no joke)

I used Zandalari Kneebiter, Ikky and MPD (like someone else above did). At the end when I only had MPD left I decided to use a decoy. Bad idea. Still killed him, but barely. Follow the Wowhead directions. 

Alsoypu need to put the entire name of the pet master or you will get how to beat him in the raid. 

got this pet 1 hardest fights cause i don't have some recommended ones at maxed. I used Hopling & Emerald Proto Drake with Mech dragon= back up. Hop vs dragon:Poison>Backflip>crush until backflip>crush to death. poison rabit. EPDvsrabit:breath>blessing>breath>emerald dream. the trick is you want to cast emerald dream when rabit uses arcane#4 so when it tries to swap it can't. if does use decoy n swap back. Rabit=star/swap/arcx4repeat EPD vs hippo: just heal/skip

I won this lil sparkly floof a while ago and kept meaning to comment and thank the those who suggested the P/P emerald proto drake. Mine was P/S and I just couldn't get it done. I went and found a P/P breed, stoned and leveled it, and SUCCESS! With Macabre Marionette first, and EPD second, using the heal/dream rotation, I got it on the first try. Thank you guys! Being a lifelong Bowie fan, this guy was extra special to have <3

Hi got this with

Zandalari anklerender black claw/ Hunting party/ Leap (dies)

yu'la exchange life/ breath until exchange back up and repeat until dead

Infested bear cub. the strat here is last pet throws up a meteor for 15 rounds, you just need to survive until it hits, so Hiberate as soon as its up. meteor hits, both pets die BUT you are undead... bingo you win

of course like so many others said i used a zandalari kneebiter and emerald proto ...start with the ZK use black claw then hunting party....switch to EPW and just keep using its heals when they come off CD while using either attack it has

I just got mine last night. Named it "Ziggy" because - of course. 

The strat I used to defeat Algalon the Observer was:

1st Pet Slot: (P/P) Zandalari Kneebiter

1st Ability Slot: Hunting Party

2nd Ability Slot: Black Claw

3rd Ability Slot: pick either one

2nd & 3rd Pet Slots: (P/P) Emerald Proto-Whelp

1st Ability Slot: Breath

2nd Ability Slot: Ancient Blessing

3rd Ability Slot: Emerald Dream

On your whelps prioritize healing EVERY TIME they are on cooldown, no exceptions.

Just got this little adorable rabbit with a strat posted by a Wowhead user.

Zandalari Kneebiter S/S (2/2/1)

Ikky (1/1/1)

Mechanical Pandaren Dragonling (1/1/2)

There's the full strat.

I managed to finish the dragon with a Leap then apply Black Claw to the rabbit before Kneebiter died then proceeded further. I guess maybe it was a matter of crits since I had none on both sides. Good luck!

I got mine today and i all ready got her to lvl 25. If you want to see a video on how to win Hazelnuttygames on youtube has the best strat. I named mine twinkle and i really love her happy hunting

I found the advice from other players good on the first too pets good. But for the third pet I used a Scourged Whelpling as backup.

Alganon is tough. I found a team that can defeat him w/ 2 pets. Macabre Marionette (upgraded to rare quality) 1/2/1 abilities. Emerald Proto-whelp (PB) 1/1/2 abilities. 3rd pet doesn't matter. Start off with Marionette using Siphon Life>Dead Man's Party>Maraca>Maraca until Comet dies. Switch to Emerald Proto-whelp and use Emerald Dream>Ancient Blessing>Breath (IN THAT ORDER). Use Emerald Dream followed by Ancient Blessing on cooldown with Breath as filler.

I'm so excited to finally have this little guy, he's adorable!  At least get yourself an Emerald Proto-Whelp before the battle before you try to battle Algalon.

I haven't really tested how useful he is in NPC pet battles, but his switching ability sure is fun in pvp.  :)

Finally got this little cutie today and I couldn't be happier. I haven't battled with him yet so my review is based solely on his appearance and animations and just on that alone he's a winner to me!

I mean how can you not love a star bunny that turns into a star, flys into air and then crashes back to the ground next to you as a bunny

Cheers Falconarc great advice worked a charm.

As difficult as this battle first seems, just two pets are needed:

Flayer Youngling (S/S) 1/2/1

Emerald Proto Whelp (P/P) 1/1/2

See my post on wowhead for the full strategy!