Advance Wars: Days of Ruin/Days of Ruin

Official Tactics
Position your units beside the enemy and attack them.

Guide
This stage is pretty stright forward and the in-game tutorial will guide you though. Don't worry, you can't really be defeated here if you use common scene.

When you first start off, you have Ed in the motorbike against a infantry, recon and a motorbike. Follow the on screen direction and move your motorbike as far left as you can then end your go (by going onto the map menu and clicking 'end turn'). In the next turn, your reinforcement in the form of a tank and a recon arrives from the left. The motorbike will now move off the screen leaving you with the tank and recon.

Now that you have the tank, there's no way Drakov can win so don't panic. I would suggest that both your recon and tank attack the enemy infantry unit. The enemy units will start running away from you during their turn. I would now attack the recon with the tank whist attacking the motorbike unit with the recon. It will take two turns for you to be able to destroy them.

After two turns, you should have destroyed the enemy units and earn yourself a nice Super Rank for this simple mission.