Well, the Magic card market is finally rectifying that mistake.
But why the sudden price jump? Is there something in Battle for Zendikar that suddenly makes Zedruu even better? There is one Minotaur in the set, Ondu Champion, but he's an Ally, and unless Zedruu is going to be a good Ally Commander (quite doubtful) that's not it.
There are a few other cards in the set that Zedruu decks could play, such as the Blue enchantment Retreat to Coralhelm which can either tap or untap a creature or let you Scry. But that's not something you'd want to give away.