Enemy army #1 showed up just in time to trash my first expansion... I had my own army, which tried to engage it, but somehow his smaller force of marines with no upgrades killed off my larger force of slightly upgraded marines with no losses. I watched the replay and still don't know what happened there. Anyway, I eventually killed off some of the marines with the flamethrower go-karts and finished off the last few (when they started blowing up my factory) with my SCVs.
Then I rebuilt my expansion.
Then I built another expansion, for the heck of it.
Then he attacked me with WTF invisible airplanes that my units refused to fire back against. My initial base was destroyed, but it was out of minerals anyway and I evacuated all the buildings. And built two more expansions. Then the invisible planes destroyed one of my expansions, and another. I built two more expansions. I got sick of the fucking invisible planes and discovered the 'scan' feature that let my units shoot back at them. THREE ARMIES (and several destroyed bases) LATER I finally destroyed most of them because it's really fucking annoying to have to manually scan the area that I want my people to fire back in, and he just flies out of it again anyway so wtf. Is there a unit that maybe detects cloaked things or something? I didn't see any of them mention it in their short descriptions.
He built more. They were never quite as devastating again though. He did manage to completely destroy one of my bases with four vikings because my army was elsewhere chasing invisible planes, though.
Then the game ended due to time-out or something, and I was declared the winner, on points, because while I'd been flying all over the map building expansions and getting them destroyed and building more, he'd been sitting in his initial base building OMGhax invisible airplanes and only built 12 SCVs during the ENTIRE GAME which isn't even enough to efficiently mine that one base.
Aaaand his APM was... 12!