The war broke out several hours before sunrise, the time when people were the weariest. The guards saw at least a regiment of heavily armoured vehicles with their telescopes: these machines loosely resemble the Fire Nation's tundra tanks during the Hundred Year War. "Inform the Great Uniter! We need air support!" the captain ordered his lieutenant, as he sounded the alarm. A company of soldiers in metal helmets and tactical body armour quickly formed a line of defense on each rings of the ramparts, firing the grenade launchers to the incoming attack.
The explosives weren't very much effective against the vehicles, as these machines were obviously protected by a thick layer of platinum. It took at least three consecutive shots on the same spot to create a small opening on the armour.
"Aim at the cannon, that's the weak point!" the captain followed the voice, the person has launchers for metal cables and extra metal shards as ammos equipped on the back and the sides of the armour, the signature looks for the Special Forces. She was holding her telescope with a metal hand, the rank imprinted on her helmet indicates Colonel.
The Colonel's methods worked, as the cannon was not as heavily shielded as the rest of the vehicle, it only took one of two shots to damage the weapon. It was a move that kills two birds with one stone, as the explosives not only penetrate the armour, but also nullified the enemy's ability to retaliate.
"Colonel Kuvira!" asked the captain, "what do we do now?"
"Take cover!" said the Platinum-bender, as the enemies were about 200 meters away from the outermost defensive wall, "their weapons are now in range!"
The enemies' machines started to shoot out pressurized flames from the cannons, creating openings on the parapet. The earthbenders quickly replaced the damaged spots with rocks from the ditch. Soldiers had to resort to a more defensive move, as they were limited to fire their grenade launchers behind the embrasures. As a result, their firepower was compromised. The armoured carriers advanced in their position.
"Special Forces Dispatch 1 and 2, reinforcement to the outer and middle ring," Kuvira radioed her troops, "Dispatch 3 and 4, biplane air support!" She blocked an attack coming for two soldiers with a rock, the earth exploded and was reduced to pieces.
Within two minutes, two battalions of metalbenders set foot onto the parapet through metal cables. They brought more portable grenade launchers with them, aiming at the cannons on these machines, while evading the enemy's flames, or bending pieces or earth to block the incoming projectiles.
The Colonel ripped the cannon off of one of the armoured carriers, launching it into the swarm of machines like a spear, creating a serious explosion in a dozen of vehicles.
"Too bad for them, we have a platinum-bender." The woman had the symbol of the earth element, the national emblem of Earth Republic, imprinted on her helmet. It was Suyin, the Great Uniter. She fired her weapon, the explosives landed onto the cannons with accuracy, destroying a couple of enemy vehicles in a matter of seconds, "that's what they get for messing with my country!"
At the same time, they heard the sound of engines, two squadrons of biplanes appeared in the sky. Dropping explosives into the swarms of enemy troops. The enemy immediately reinforced their armoured carriers with a battalion of mechasuits.
The mechas were far more agile, they avoided the attacks from the above with ease, and retaliated with their enhanced version of flamethrowers. The United Forces equipped their military with the crystal that magnifies the power of firebending. The power coming from these weapons were no less than that of a combustion bender. The biplanes countered with their own grenade launchers, but their attack wasn't effective.
The enemy brought an airship to the battlefield, a figure launched itself out of the aircraft. Instead of opening a parachute, the person extended her arms, circling in the air with her wingsuit. It was the avatar.
With the help of her airbending, Korra took a sharp turn of the direction of her flight, landing herself onto one of the biplanes. Then, she shots jets of flames from her fists, breaking the biplane's engine. The pilot jumped out of his plane, without the power of its engine, the plane swirled its way to the ground. The avatar opened her wingsuit, moving onto her next target.
"That's no good!" Suyin said as she saw the avatar hijacking the biplanes, taking them down one by one, like a falcon. Losing the air force only decrease their firepower further. Now they had to rely on ground forces. What makes the situation worse, the airship started its attack on the city wall. With only firing its cannon once, it destroyed one of the bartizans, removing a huge chunk from the terreplein.
"Focus on the ground force!" Kuvira spoke as the enemy's vehicles had reached to the bottom of the city wall and started to drill their way through the defence. "I will take care of the airship!" She launched a metal cable to the aircraft, barely avoiding streams fire shooting from the cannon. As soon as she landed her foot onto the metal contraption, she started tearing open the ship's platinum covering.
The Platinum-bender was nearly knocked off her feet by a strong gust of wind. She blocked jets of white flames aiming at her head with metal shards as she managed to cling onto the airship's surface. The avatar was coming at her.
"Surprised?" Korra landed onto the top of the airship, lashing out whips of fire at her opponent.
Kuvira used her metal cables to swing her way out of the attack and regained her footing on the top of the airship. With a flick of her wrist, Korra changed her attacks into fire missiles, the flames changed its course, following the movement of their target.
The Colonel closed in the distance as a response, launching her platinum hand at the avatar. Korra had no other choice but to retrieve her attack of fire missiles, which was replaced by a wall of flame, moving its place to Kuvira.