OK First Off Sheep Pet - VIP Pet (KI picks players to have it) Pioneer Dragon shouldnt have been said, because there is no way for anyone who dont test the game to get it. Frost Hound - Was a Bug that lasted for about 24 hours, and KI let the pet stay in game. (there are a total of 3 people on Wizard101cental with one)
Now if you would really like to have a Rare Pet, Try for the Fire Beetle in the KIfreegames.com you have to have a very high score. But if your looking in game I would say NONE!! Most pets are now hatchable so anyone can get them, if you are a die hard collector like myself then you should go and collect the Promo Pets (unless you have them) There are also the PVP Pets which I dont see alot of people running around with, might wanna try for them.
You guys need to start reading the dates of the post before you try to correct them. Currently I would say the beta fish and trojan horse, though in a months time it will probably be very common. I want one ^_^
I wouldn't consider the Trojan Horse or the Betta Fish rare because they came out a few days ago with the bundle, it'll get more popular in a few days. I consider the Gob-o-Lantern the rarest pet in the game. It's like I'm the only person with that pet
Probably a first-generation FOG unicorn or something like that, that never hatches itself as the product of a hybrid hatch.
I work with a death who has a Scarecrow pet that gives a Scarecrow item card. I don't know much more about it other than it has a purple and gold-trimmed robe, not a sooty black one. So it may be a different pet.
I do wish some rare promo pets had a small chance of reproducing themselves via hybrid hatching. Storm beetle would be nice although most of the time, the rain beetle you get is a better pet.