So there are many dialects of Japanese around the country, the ‘standard’ Tokyo/Kanto dialect and humorous Osaka/Kansai dialect being the two most recognized.
Some nifty Kansai-ben (as it is known in Japan) phrases I’ve heard:
なんでやねん (nande yanen) – What the heck?
ちゃうちゃう (chau chau) – No, no (that’s wrong)
ほんまや (honma ya) – No kidding/ That’s true!
あかん (akan) – That’s bad!
There are many other dialects around Japan, if you’ve heard of any/know some cool phrases let me know!