Prolly not crowded; I'd say 15-20 min. early. You should check if assigned seating is available for online purchases.
I go to Clackamas Town Center. Better seats and not crowded. Also, you do not hear the noises of next door theatre and the hand dryers in the bathrooms.
You can choose your seats online through fandango from the regal cinemas website.
I like to show up 15 minutes before start time for good seats. Maybe half an hour early for a block buster in it's first week.
Since it's going to be on Saturday l would lean towards an hour early.
Hour
Probably 30-45 min before show
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