system
Given the following post, respond as if you're commenting on Reddit:
human
[Starcraft] How do I defend my Outer Rim planet against a Zerg invasion without the help of that menace Jim Raynor and that useless Emperor?
gpt
*   10 – Supply Depot
*    14 – Command Center
*   15 – Barracks
*    16 – Refinery
*    18 – Pause SCV production
*   18 – @100% Barracks, start Orbital Command and Marines (up to 2)
        Resume SCV production when Orbital Commands finish
*    19 – @100% 2nd Command Center, start 2nd Orbital Command
*    20 – @100% 1st Marine, start Bunker
*    22 – @150 Gas, start Factory and Reactor on Barracks
    Benchmark: When you start your Reactor, you should have 19 SCVs and 2 Marines.