Simple Pet Dupe (Patreon)

Each major race in wow has a specific battle pet associated with it - only a member of that race can purchase the pet from the relevant battle pet npc in the appropriate faction capital. The Pandaren pet, the Jade Crane Chic, sells for over five thousand gold on average. This is mainly because you have to run through the pandaren starting zone to get one which takes time. 

Pandaren death knights allow us to completely bypass this requirement. Use the following method:

1. Create pandaren death knight, the faction must be horde

2. Accept quest  "Death's Power Grows"

3. Swear fealty to the Lich King

4. Turn-in quest (remember to select weapon)

5. Accept Lich King quest "Defender Of Azeroth".

6. Speak to Highlord Darion Mograine

7 Use deathgate.

8 Mount up, go left at the Orgrimmar entrance to the Orgrimmar Embassy.

9. Find Matty the goblin battle pet trainer.

10. Select his option "interested in catching some rare battle pets".

11. Learn jade crane chic pet.

12. Delete your character.

12  Repeat.

You can have 3 crane chick pets in your journal. If you try and learn more nothing more will happen.

If you want more than 3 you can try putting one of your existing crane chics in a cage. To do this:

Open your pet journal, find the chic's, right-click on one of them, and select the option "put in cage". This will be added to your inventory-you will now be able to purchase another chic from Matty.

You can sell caged pets on the auction house. The chics sells for an average of over 5 thousand gold. 

The chic's do not sell especially fast but there is a market for them. The caged pets can also be sent to alts, even characters on other realms (in the form character name-realm name, so for example Archvaldor-aerie peak) . 

Sophisticated players may wonder why I am not mentioning the use of class trial characters to bypass the pandaren starting area (or for that matter goblin and worgen starting areas). Though this works well, in 2020 there are so many gold-making exploits that  you can do with your class trials, that it would be a poor use of a class trial to try that strategy. Also, there are severe limitations on class trials which do not apply to death knights-you hit the class trial limit very quickly. Using death knights you can create infinite chics.