Select the four units (3 reapers + 1 grunt) move them to the east in small movements until you come to a crater.
Destroy the blue grunt that you find there.
Continue moving to the east until you meet the commandant.
Select all your units and set them to high initiative then move them all to the beacon at the south eastern side of the map. (click on the scanner map directly). They should destroy a few units on the way.
Defend the base and build a constructor.
Build a level 1 military factory (light infantry) and the reapers required to win.
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