u/werp2_5

I started making a language for a highly advanced alien civilization. I want that language to be otherworldly, but I struggle with creating a case system that doesn't look too normal. My first idea was to have six cases: Nominative, Genitive, Accusative, Dative, Lokative and Vocative. (I don't really know a lot of cases so I was kinda going with the ones I am familliar with) The thing is, I think it looks too much like an indoeuropean language's case system. Have you made an exotic system or do you have any ideas for one?