I would say that the Plant engine is more pivotal than the Zombies. The Zombies can literally win you games on turn one if you play it right, but Spore allows you to go into the 3rd Omega (which will be easier once we get the Lightsworn link in a couple weeks because it's a foolish burial on summon), and allows you to create a board with at least a Minerva/Tornado Dragon and Decode.
