It’s unclear whether or not Hypnotic Pattern will work in the dark. As prepared, It could be up towards your DM to make a decision. Individually, I'd personally rule which the Hypnotic Sample is made of sunshine as it's an illusion and would, as a result, be noticeable at nighttime. https://patronhipnotico43208.bloggactif.com/35680701/patron-hipnotico-an-overview