What is the funniest joke in the series?

Sally

Aw nuts!
Mario is a good humored fellow, make sense that there would be a lot of funny moments.
So, what would be your favorite joke in the entire Mario series, sub series included.

Personally, I always crack of Mario & Luigi "Italian" gibberish in the rpg series
 

JBX9001

IT'S-A GO TIME, MO' FO'S!
Oh gosh, there's just too many to choose from to pick just one! But one of the funniest overall has to be that one Bowser segment in Paper Mario: The Thousand-Year Door where he encounters Lord Crump at Twilight Town. Shots are fired, they call forth their respective troops, Crump throws the Super Bob-omb to no effect; only for Bowser to foolishly set it off with his fire breath and... We all know what happened next...!
 

Dark Light

Cherries and Berries

the game is filled with moments like this, with the babies being so charmingly stupid and unintentionally getting luigi into shenanigans that i love it
 

Brawl Mario

Super Smash Bros.'s most fearsome plumber
I really like the part where Wario-Man gets slammed by a train and he yells "LAAAAAMEEE" and then he gets conked in the head by the Sewer Guru.

There's also the instruction booklet on WarioWare: Touched that I like.

Knock it off! Get your grubby hands off the Touch Screen! Whaddya think the stylus is for?! USE IT!
"Quit bangin' on the Touch Screen! Unless you wanna break it... If so, go right ahead!"
"Stop touching the top screen. IT WON'T WORK!"
 
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