How does rage fist hit counter work when engaged with multiple wild Pokemon?

Apologies if this has been asked already but I didn’t see any posts during a quick search.

In previous games, it’s pretty clear when a battle is over, the hit counter that builds up power for rage fist resets. But in LZA where battles (especially wild battles) are more free-flowing and you can be engaged with multiple Pokemon, it’s a little less clear. Has anyone figured out when the hit counter resets?

Marked spoiler in case people don’t know annhilape is in the dlc.