LefyBoy responds:
You can't infringe on Copyrighted material if the custom content isn't making money. QQ more.
you absolutely can...
Look under the fair use law, its extremely iffy, so they (nin.) could send you a C+D letter for you to stop just off of the grounds that you are using their sounds without giving credit to Nintendo. The same exact thing happens all the time with websites that upload pieces of music made for remix contests (called "stems") after the contest ends. Also, there is the fact that you are using their sound in an animation that later on you could show as part of a portfolio.
5-2=3 stars for dumb video with horrible sound... 3-3=0 stars for being an asshole to the guy that warned you about it.