It’s unclear if Hypnotic Pattern operates in the dead of night. As published, It will be up to your DM to choose. Individually, I would rule that the Hypnotic Pattern is manufactured of light as it is actually an illusion and would, as a result, be seen at the hours https://manuelbhmru.howeweb.com/35005617/the-smart-trick-of-patron-hipnotico-that-nobody-is-discussing