Has anyone tried this one out yet? I've fought against it, and am now using it for 2 days.
The tactic is pretty simple: Creeping Fungus (undead attack) > Stampede (critter attack)
When stampede runs out, refresh creeping fungus and stampede again untill you die.
If you fight humanoid, the stampede is weak, but strong Creepign fungus with double damage takes care of that (it already ticks for 200+ on non-humanoids).
I think it's weakest against water.
But overall I'm impressed with how simple it is to "use" in combat and its effectiveness. Don't forget you're almost guaranteed to leave the enemy with a double damage debuff for 2 rounds because of undead racial. so even if you somehow loose a 1v1 battle. Your next pet will probably kill it with ease, and if the enemy swaps pet, well you got a free attack

If you actually killed your first enemy, leaving the next enemy behind with a 200% debuff is priceless.
I would actually like to hear some ideas of decent counters for it -> preferably pets focused on damage, not healing or shields (They make longer battles, and I don't enjoy the slow playsyle :p, I use raven, Infected Squirrel, Death Adder Hatchling atm). I used to have Jademist dancer instead of Infected squirrel, but it feels easily countered.
I've not seen this pet a lot yet. But I AM seeing it occasionally, and I wouldn't be surprised to start seeing it more.