Once you unlock the blasting ability of the spear of adun it gets a LOT faster to clear objectives. Its like sending a baneling wave into a hard point and melting most of it before your army arrives. Suddenly the choke point is defenseless and there is little there to stop your squad from getting up the ramp. Really reduces the forces you need build before you attack when you arent going to lose several trying to bulldoze through a bunch of bunkers or photon canons or whatever. Its honestly funny how broken the campaign only stuff is in swarm and void. Kerrigan can virtually solo stuff end game, and the spear has so many major abilities that make things go so much faster its nuts. The terran stuff felt a lot more subdued but still powerful with the research and the upgrades you could buy from swann.