Steredenn: Binary Stars

A "Spy" is a little black enemy that phases in and out of sight while laying mines. They typically begin showing up on the fourth stage. Just make sure you grab the Flamethrower as early as possible should it drop from a Cargo ship. To improve your chances, you can always use the +1 Cargo per Stage upgrade if you happen across it.

I got this without having the flamethrower equipped, I believe the fire hyper blaster did the trick, I only ever picked up the flamethrower twice. The fortress ship comes with a fire blaster so that should work as well, and the spy is a tiny little black ship that lays little red mines and kind of blinks. I had given up on this when it popped and was very surprised cuz I did not have the flamethrower equipped, hope this helps.