How to write the correct regexp?

Excuse me, I've a picture named "game.png" to be replaced and it's name is game-8397.png in Data folder.

I'm new to regexp so I asked Chat-GPT who gave me "game(?:-\d+)?.png" . After running "keynote-parser replace test.key --replacements try.json", nothing happened (I also tried "game(?:-\d+)?").

So how should me write the corredct regexp? Thanks in advance!