I moved my Marshall one piece ahead to see what he would do. I had suspected that the piece next to (left of) his general was his spy. Instead of moving his general this time, my oponent moved another piece trying to set up another front. This strongly indicated to me that the piece to the left of his general was his spy. He was just waiting for me to attack his general with my marshall.
This was my move instead. Since I only moved my scout one pace, my oponent had no idea what piece it was. He continued moving pieces on the other front, not suspecting I was still concentrating on his spy and general.
And then, I set up for the attack. Again, I only moved this piece one space. By this time, it was pretty much too late for my oponent to do anything to counter my attack, anyway.
My final move I used my scout's attack by distance property. We usually play that the scout can move and attack on the same turn. I believe the rules say players can only do one during a turn. It does not matter for this move. The least consequences either way for you would be that you trade your scout for your oponent's spy.
If the game is left in the position shown above, your oponent has a few options. In all, he will lose a stronger piece than you.
1. If he moves his spy back, to protect his spy, you take his general out with your marshall.
2. If he moves his general back, to protect his general, you take out his spy with your scout.
3. If he doesn't move either piece, attack his spy with your scout. You will probably lose your scout, but that's what scouts are for.
4. If he attacks either of your pieces, you win both pieces.