Oh that.
For defense, deploy 3~4 Defender VXs in Airdestroyer mode to the north of your base and keep them in tip top shape. A Tower near the closer land bridge backed up by two Defenders should stop most assaults on your base. The nanoswarm core can stop the Proton Collider from hitting your base, use it to shield your base when it fires, or you can use Final Squadrons to take out the powerplants behind each superweapon to neutralize it.
I used a mixed force of King Onis, Imperial Warriors, Tank Hunters and Yuriko to cover a few Wave Force artillery pieces. Striker VXs on the ground to cover the air. You should level every building in the Allied air base so that your artillery will have clear firing lines.
When you level the air base, a pair of Chopper VXs and 4 Rocket Angels will come in from the south.
Keep an eye out for Tanya, you'll need Yuriko's sheer power
to keep your force alive. Add to your forces as you see fit. Once you clear the airbase, you can proceed north and east to the Allies' stronghold. Just level everything in your way, civilian structures and all, and cover your Wave Forces.
After you severly damage the Future Tech building, the Soviet scientist will unleash some weird weapon and wipe out everything on the map, and the map will be resized to fit a smaller area. You and your co-commander will be given a pair of Mecha Tengus, a King Oni, and 6 Rocket Angels, all max ranked. Then you just have to finish off the Soviets and blow the building.
Or, you could just hold off the Allies, deploy Docks and raze the Future Tech to the ground.
If you want me to help co-command, pm me and we'll set something up.
