Croatian Language
The most dick wrenchingly difficult Russian doll of all languages. Just when you think that you've uncovered the key to understanding how to speak it there's a new level of suffixes and word re-arrangements. There's 87 common ways (excluding anomalies) of completing every single noun in this bullshit language, and at the end of it, everyone in Croatia uses one of 3 dialects which are completely separate to the actual language.
Dave: Hey, did you hear Mike's taken Croatian Language for Beginners this semester?
Pete: RIP
Pete: RIP