Unicron
Quote: "Revenge is a dish best served with pie."

He's been a floating head for too long, and he will have his revenge against Primus and his children if it's the last thing he'll do.  To this end, he's preparing Galvatron to do his bidding.  Why Galvatron, you ask?  Well, let's just say we have *big plans* for him.  Revenge is slow but sure, and when you're only a head, revenge comes very slowly indeed.