If the new Zerg from the Heart of the Swarm Expansion invaded Azeroth led by Kerrigan herself what do you see happening? Post how you think it would go down.
Keep in mind this is an interstellar invasion that has stretched across galaxies to find you in Azeroth. Kerrigan has since studied Azeroth and found our weaknesses and is prepared to make us pay for them. Likewise we have Oracles like Velen and Planetary Gaurdians such as Wrathion who have sensed Kerrigan's arrival and have alerted both Alliance and Horde of what would be the greatest battle of their lives.
Keep in Mind what Azeroth is Up Against:
Nydus Worms http://us.battle.net/sc2/en/game/unit/nydus-worm
Swarm Hosts http://us.battle.net/sc2/en/game/unit/swarm-host
Swarm Queens http://us.battle.net/sc2/en/game/unit/queen
and The Queen of Blades http://us.battle.net/sc2/en/game/hero/kerrigan
Who would be left standing?