"Piranha Plant's Lullaby (Beta Mix) - Super Mario 64 DS" is a high quality rip of the beta mix of "Piranha Plant's Lullaby" from Super Mario 64 DS.
Joke[]
The instruments are arranged into "Bonnie's Lullaby" from Five Nights at Freddy's 3 (which is in turn a rendition of Schubert's Serenade).