It does appear that Niantic will start rotating Pokémon in and out of Max Battles on a month-by-month basis, with some event Pokémon littered in.
That being said, you’ll want a healthy amount of Dynamax Pokémon in your team if you choose to divulge in the feature, as only Dynamax Pokémon can participate in Max Raids. (So you’re pretty much catching Pokémon to help you catch more Pokémon.) Notably, if you’re just starting out with Max Battles, you should have a “To the Max!” Special Research set that starts you off with a Dynamax Wooloo.
Below we list the currently available Dynamax Pokémon that you can score from Max Battles.
Pokémon Go Max Battle line up for October 2024
These Pokémon have been confirmed to be in Max Battles throughout October:
* Shiny version available.
The official announcement for October also has a mystery Pokémon in the line up, which will probably get announced fully in an upcoming event.