I won’t say that you should skip all of these zones. There are a number of pets with interesting models and a few really cool and unique pets. But the Cataclysm zones have fewer “must have” pets than the other zones, and you could probably step right onto the boat to Pandaria and be able to fill in those holes with a few good captures. In any case, let’s look at it zone-by-zone:
If there’s one zone you need to visit, it’s Deepholm. And here’s what you should be looking for while you’re there.
Fungal Moth: this Flyer isn’t any different from any of the other moths, but you may not have found a good Rare moth yet, and there are plenty of Moths here for the taking. Try and find the Speed or Stam/Speed breed if you can, but any rare will do in a pinch.
Crimson Geode: this Elemental is worth farming for a rare as it has some very cool damage abilities. Try to get the pure Power breed or one of the Stam/Power or Stam/Speed breeds if you can. Anything but the pure Stam is good.
Crimson Shale Hatchling: this Elemental is a tanky variation on a spider pet. It holds up pretty well and is easy to level, though not all that useful against the later tamers. The Crimson and Topaz all come in variable Stamina breeds, while the Amethyst and Emerald can come in any of the nine breeds.
This probably isn’t important when you’re just building up a stable, but it may be helpful if you’re farming for a specific addition to your PvP pet squad.
The other pets here are just variations on pets you may already have, for the most part. It may be worth farming for to fill out a hole, but there are probably better zones for this.
Wildhammer Gryphon Hatchling: this Flyer doesn’t have any unique abilities, but it’s got such a cute look! Don’t waste too much time farming for a rare, but an uncommon shouldn’t be too time consuming. There aren’t many spawn points, but it’s a common secondary pet.
Twilight Fiendling: this Magic pet can do alot of damage if you get the right breed. I was impatient, didn’t understand breeds, and wasted a Magic upgrade stone on a pure Stamina breed. I also haven’t used that pet very much since. There are better pets out there, but it’s cool looking and if you can find one in a Power breed it can be pretty good (I think).
If you don’t have a rare Prarie dog or Marmot type pet, this is a good place to farm for one (Yellow-Bellied Marmot). They are much more useful than you’d think when fighting tamers. Otherwise, the remaining pets are just okay.
This is probably the other “must visit” zone, especially if you’re looking for a rare moth or frog that you don’t want to level from scratch.
Oasis Moth: this Flyer isn’t any different from the other moths, but you’re more likely to come across one here than any some other zones. If you have a rare, or don’t care about moths, you can always get one in Pandaria. But this isn’t a bad place to farm or level pets and grab one.
And that’s all she wrote! What are you even doing here? Pandaria awaits!