The Great Protoon Orb was the object that kept things in Rayman's world in balance. It acts similar to our law in reality. The orb was guarded by Betilla the Fairy until Mr. Dark stole it. When the orb was stolen, the electoons scattered. It has not been seen since then in any other Rayman game.
'Protoon' is a play on 'Proton', the large, positively charged mass that, along with neutrons, form nuclei of atoms. Protons' attractive force and it's mass is what keeps electrons in its place, so presumably this is how the Great Protoon Orbs effect was inspired by Ubisoft.
This is also similar to the electoons, they are a play from electrons, the charge of atoms are caused by friction.