This should be main strat it worked super easy and as you said third pet not needed. Using above strat with water spirit and razor even with a pet that did beast damage in 3rd slot I could not get it to work at all.
- Blistering Cold until Maul is up the second time
- Aged Yolk to clear Rip before Maul lands
- Blistering Cold until Carrot is dead (you want to make sure this debuff is up as long as possible)
- Swap in Fetid Waveling
- Poison Spit
- Corrosion (unless Maul is available to Gnasher, then Healing Wave)
- Healing Wave if Maul not used prior round
- Poison Spit until Waveling is dead.
- Tiny Twister comes in - Call Lightning
- Slicing Wind until Gnasher dies
Thanks for the tip to use Cinder Kitten.
I opened with the Pandaren Water Spirit and followed the above strat.
When Water Spirit died, I brought in Fel Flame (2, 2, 1). Scorched Earth, Flame Breath, Conflagrate, Fel Flame dies, bring in Cinder Kitten.
Cinder Kitten (1, 2, 2) Leap, Rend, Gnasher dies.