Last edited Dec 14th 2022
For its time (2008), the animation is really good, and still is. It blends 'traditional' Flash animation with sprite animation in certain areas, with custom Miyamoto sprites in at least three different games.
The Flash sections use very minimal animation, some motion tweens are used, and a few imperfections in the outlines are noticeable, a common problem with Flash movies of the time, but it's still well-shaded.
The music was replaced in May 2022 for copyrighted reasons, (originally the Fatboy Slim song "Gangster Tripping"). Unlike what @LiteraryWho said, it was @Recorped who swapped it out with something more Nintendo themed, although I did consider making an original track (I got lazy).
However, it did still credit the old music, so I hand-drew the new text. That's the only involvment I can claim here outside of a lengthy PM conversation regarding other removed submissions.
Also presumably as a result of being removed for so long, its score of 4.86 managed to get preserved well enough to put it in the top 50 movies of all time, beating out Tarboy and several Madness movies.