My first game with an actual goal. Recruit troops, fight a round, find out how good your choices were. The composition of your army decided how many troops you lost against that round's enemy.
I didn't know what a loop was, so every round was written out by hand. Another round meant another stretch of code. War Arena became one of my longest projects at the time, and the first game I built myself from start to finish.
I was so hooked that, before going to the Le Mans Classic in July 2008, I printed every page of War Arena's code onto A4. With no loops and every round written out in full, that was a huge stack of paper. It didn't stop me. While I was away I kept working on it with pen and paper, writing fixes and improvements by hand to type up once I got home.
When those were in, I started Outscape ~ The Annhilation.