Each battle that you win will yield experience for each pet that participated. However, deceased companions will not receive any experience (so make an effort to keep them alive by swaping in a different pet). Experience gains are based on your pet's level compared to the wild pet. Defeating a higher level opponent will grant more experience than a much lower level one, but be ready for a tough fight!
Hey folks! I’ve got a small update here to help quell some of the rumors and let you know where we are at for WoW Classic. We recently began a phase of internal employee alpha testing. The new build data that many of you have been discussing over the last few days is simply part of this process. Phases like this allow us to test out the game content along with other functionality that will be used in the live game, like logging in through the Blizzard Battle.net 175 App.
It was the experience of the game that brought pleasure and joy, and that's what a lot of us want again. Not the numbers. When I play Classic I want to go through the deadmines with people I like and overcome a challenge together and see myself become stronger as a result. I don't want to play Classic so I can say "booyah! That number is exactly the same as it was 13 years ago!"