Warehouse
The cases have a plain aluminum shell with what appears to be barcode etched into their lid. The inside of the cases has molded foam which appears to be shaped to it could hold one duckification riffle and a rectangular box (possibly a power pack).
Oblivious to Psiren's psychic chicanery, Prodigy 'hmms' as she opens a couple of cases and confirms that they're empty.
"This must be where they got the rifles before attacking. Maybe I can crack this barcode once I get it back to my lab..." Then she realized. Rectangular box. Power pack. Power pack!
She triggered another configuration change in her suit, extending its sensor enhancements and bringing its passive EM and anomaly detector array online. Then she made a sweep of the warehouse, scanning for the thermal and electromagnetic signatures of energy sources nearby.