Hey there @Starburst-The-Hebi, welcome to the site!

To change your current adventure pet:

1. Have your current adventure pet travel back to Gateway City, and then go to the Entrance Gate and click "Finish Adventure." This places the pet on standby.

2. If you don't already have other pets in your adventure squad, you can assign them from the adventure squad page.

3. After assigning another pet to your adventure squad, head back to the Home page. Find the pet you want to adventure with, and click Start Adventure.

Please let me know if anything I said was confusing or if you have further questions! :)