ok this is a famous tip as used by BoXer.Put a ghost, 6 marines, and a medic in a dropship and drop em off at your enemy base. have the marines and medic distract the base defenses(this will only work for a bit) while the ghost cloaks and sneaks around to nuke the enemy workers(scvs,probes,drones) by the time your marines and medic are dead, your enemy should have a messed up base!