Mario has defeated the Koopaling at the end of the castle. Now, as he did every time, he intends to blow up the castle thansk to that here detonator. However, the castle doesn't want to be destroyed. As a result, all of Mario's attempts are failures.
This series s a rapid-fire comedy, with all the attempts being barely a few seconds long. The series is available on Newgrounds and Youtube, although lots and lots of fan versions were made as well.
If I can make one point of criticism, sometimes the comedy dares going into dirty comedy... but overall, the series is still fun. Of course, it could get tiring after a while... The concept stays the same all the way through. Luckily, the Mario uiverse is complete enough to provide a few hundred possibilities for jokes. And sometimes, just add stuff from other games, and the problem is solved!
The first video can be seen here, the second one can be seen here. The series was so popular that it spawned lots and lots of imitators. Among others, one that has Luigi trying to crash the castle. Two collaborations were made with different animators.
Last but not least, a contest of Mario's Castle Calamity was made with a program called GMOD. The result? A LOOOOOOOOOONG video.
Enjoy this slapstick series!