An unreleased Game Boy port of RockBoard has surfaced this morning following another batch of "Nintendo Leaks."
The game is a near 1:1 port of the Famicom party game and appears to be largely complete.
I cannot directly link you to the leaked file at this time. Sorry! Look around a bit and you'll find it. Nevertheless, this is history!
We will have a more thorough analysis of the game soon. Stay tuned!