Terran

• Terran players can Yamato these defenses from a distance using Battlecruisers.

• Cloaked Ghosts might be able to sneak some Lockdown casts onto the units up high.

• Siege Tanks with Defensive Matrix can be brought in. The Defensive Matrix should give them time to  move into Siege Mode. Another Defensive Matrix can be cast on the Siege Tanks if it starts to wear off. A Scanner Sweep can spot for the Siege Tanks so they can fire on the units up on high ground.

• Dropships with Defensive Matrix on them might have time to land Marines on the high ground.

• A nice thick defense of Bunkers filled with Marines should allow you to defend your town until you can make Siege Tanks or build lots of Vultures, which are very effective in countering large amounts of Marines.                                                    Research the Spider Mine upgrade and start laying Mines also. Be sure to repair your Bunkers, Tanks, and                                                            Vultures to keep them in full form.

• Use Guardians to attack these formations from a distances. The Terrans will be forced to come out or die.

• Use Queens to Broodling Siege Tanks, Marines, Goliaths, and Vultures.

• Use Queens to cast ensnare on the units up there to make them fire slower. This won't touch Marines in Bunkers however (a good spell defense).

• Cast Plague on units up there, that should soften the units up enough to attack. A group of SCVs can quickly reverse this spell however if the attack is not immediate.

• Your best bet is a lot of Hydralisks from at least two Hatcheries. Make sure you research Grooved Spines in the Hydralisk Den to give your Hydralisks a greater range. If the enemy insists on continuing to build nothing but Marines, build Queens and cast Ensnare on the Marines. This should allow you to overpower them without taking severe losses. Then build Guardians which should be able to fire on the Marines at greater range, killing them easily and quickly in numbers.

• The Templars might be able to sneak a Psionic Storm on the units above if they are tied up in combat.

• A Large group of Carriers or Scouts can break through this defense if the Carriers are not locked down.

• Use an Arbiter to cast Stasis Fields on units on the High Ground. Then follow up with a Shuttle landing of Archons or Zealots.

• Build 3-4 Gateways and a lot of Zealots. You can use multiple Shield Batteries to extend the life of your Zealots. If the enemy continues with this strategy, quickly build Reavers with the Increased Reaver Capacity upgrade. You can kill as many as 8 Marines with one Scarab if you are lucky, and a pair of Reavers can wipe out huge groups of Marines. Archons also work very well against Marines. While you are building Zealots, you often save up a lot of gas. Use this gas on Templars. Cast Psionic Storm on groups of Marines, then use Templars with no mana remaining to make Archons which will quickly work through the large groups of Marines