In StarCraft: Survival Mode, you will be fighting against waves of enemy forces. Each round gets harder as the game progresses so you are going to need to know a few things before playing.
To start off your defense you should cover up the front with whatever units you start with.
The most important thing to defend is your SCV Recruitment station, this allows you to create units.
Let's do a quick rundown of all of the COMM Stations that will be in your base.
The Squad Support station allows you to build a Marine, each Marine costs 350 gas.
The SCV Recruitment Station is the most crucial aspect of surviving in this game. If you lose this COMM station, you will no longer be able to purchase units. From this station you can build SCV's for 160 gas.
The Explosives & Sentry Station allows you to build a Cannon Specialist (690 gas), a Sentry Gun (500 gas), and a Riot Unit (900).
The most important COMM Station is the Elite Unit Recruitment. This station allows you to purchase Attack Dogs, Dragoons, Artillery Guns, and Goliaths. We will go over the use of these units later.
Now we will go over what the SCV is able to do.
As you can see, the only thing we are able to build with the SCV is a Automatic Air Turret. The Automatic Air Turret allows you to destroy air units. Each Automatic Air Turret costs 750 gas to build.
Round Strategies:
The Juggernaut is a heavily armed unit who can do alot of damage! If he gets in your base, he will destroy all of your COMM Stations, immediately hindering your ability to purchase certain units. Be very careful not to let Juggernauts in your base. The best way to defend against them is to use Stim Packs.
Air rounds can mean life or death for your team. Building Automatic Air Turrets near your COMM Stations is always a good idea!
Elite Unit Recruitment Purchases:
In the Elite Unit Recruitment you can buy special units that do not take up unit slots.
Using the Cannon Specialist:
This is how you should play StarCraft: Survival Mode. Obviously the gameplay will change depending on the map you are playing.The best thing to do is master each map, start with the first one and then move up from there.