The floating Krystal head, and two versions of Krystal's Staff have been ripped from Star Fox Adventures.
The proper adventures begins in AbbyStabby's reimagining of the Star Fox game.
Several videos of the unreleased version 4 progress.
The fourth Star Fox: Event Horizon demo is now available with several new vehicles and lots of levels.
DanSweeto summarizes the reasons why Krystal would work as a Smash character with this cute animation.