WASTELAND
Office of the Colonial Magistrate
Mar Sara Colony
Mission Objectives: Find Jim Raynor.
Build a Barracks.
Train 10 Marines.
New Units: Terran Marine
Terran SCV
New Enemy Unit: Zerg Zergling (Fenris Brood)
Special Unit: Jim Raynor (enhanced Vulture)
It's been a while coming, but here's your first real mission. All your units start in the upper-left corner, and your base lies in the lower-right corner. Group the marines and hotkey them to 1; do the same with the SCVs and hotkey them as 2. Send them southeast, marines first, and kill any Zerglings you come across.
Going south, you'll meet Raynor. Take the entire group down to your base, then have the SCVs mine minerals while you build some more. Build a Barracks and just start training Marines. If any Zerglings attack, your marines can hold them at bay. Once you have 10, you win! (Didn't think it'd be hard, did you?)