Great game! I used a virus attack in the middle of southern Africa, then an atomic bomb covering the north-western part, and finally a chemical weapon that spread out to catch whatever was left.
I figured out the notes and the melody is stuck in my head, but I do not know what song this is.
All the melodies that I can think of that are in a three beat feel that are in a minor key are Greensleeves and Scarborough Fair.