Slovene grammar and the language itself seems to be the oddest and of the more complicated out of all the Slavic languages.

Reasons:
- Spelling and phonetics.
For me it sounds as if a person wanted to learn Italian but ended up learning a Slavic language with heavy Italian influence.
- Grammar
You know, it’s like an axiom: the more phonetic the language gets the harder the grammar becomes. If you don’t believe me, remember the Finnish and the Hungarian languages.
- Lexicon
What is your first thought when you see the word “šprehajam”?
As a Slavic person, you don’t think about abything.
As a European person with some knowledge in German/Germanic languages (English not included) you might think this is somehow connected with the verb “sprechen”(“to speak”)
Pff, hell no, it means “to go”.
You can argue with me saying there are a lot of “strange” words in all the Slavic langauge but for some reasons I’ve run into the majority of them while reading about the Slovene language.

https://youtu.be/uh2idqi6-zM
https://youtu.be/_M0JX4R2Imk