Advance Wars 1+2: BHR Mission 18

The mission everyone usually waits for. You will find the Neotank map here in one of the southwestern cities, and it is very possible and easy to end the map by destroying all of the cannons before you even reach that city.

Now, this map is significantly different from the GBA since Adder has to follow fog rules. You are able to trap him if he overextends, and he can't destroy your initial units as easily if you take a defensive stance around the starting cities. Just make sure you watch the factories and let him largely come to you.

Once you crush his advancing force, he won't have any additional units created per turn unless he gets the port or factory. This means you just need to carefully advance against his cannons and the indirects guarding them. Once you get past the base in the middle of the map, you may activate his air units and have to deal with them. Still, at this point you should be able to create some powerful units and drive him back as long as you don't overextend.