What would your character do in this situation please Read the description [Any Literacy]

How would your villain character be like while fighting against my oc to let you my main oc are like Shazam for people who Don't know is that Shazam is kid when give powers turn superpowers adult mix of Yu-Gi-Oh where a spirit possess the main character that My oc is in same situation. Anyway what would your villain character do while fighting against my oc they turn back to they normal form they normal form being teenager or preteen.