After the failure of the first invasion on the Fire Nation, the freedom fighters from the Earth Kingdom and the Water Tribes get captured by the Fire benders. Some are imprisoned in cruel prisons while the others are executed or made slaves. The Avatar Aang, Katara, Sokka, Toph and several others make their way to the Western Air Temple in order to find refuge from the cruel Fire Nation. But, before they reach the Temple, they encounter a man, who reveals to everyone that Airbenders still exist. He also reveals their location to be underground, nearby the Earth Kingdom where they had lived for more than a century. These mighty benders had made allies with many Earth and Water Benders and the whole had been living underground to avoid the Fire Nation….until the right time was upon them to fight back!

The travellers travel to their secret underground base, which they found out to be more of a great underground city. When the news of the current events are revealed, the leaders of the underground community decides that this was the right time to attack the Fire Nation and gain control. Reasons are the Fire Nation being weakened after the invasion, and also, the new invasion to be totally unexpected. This time, the force to battle the Fire Nation was much larger than ever. The Gang agrees to the proposal, and they prepare for what would be their last chance to gain control.

After a five day wait, the great army of freedom fighters attack the Fire Nation, and they achieve a great victory. Meanwhile, at the Royal Throne Room, Aang faces Firelord Ozai along with Katara and Toph. Zuko faces his older sister Azula. Both the battles are won by the good side, and Aang is looked at the face of a bruised and battered Ozai.

This battle is not over…….Avatar! I will have revenge if I live, and if I don't, somebody will seek vengeance!! Remember Avatar, this is not the last battle you would fight, this was just a little appetizer!

Those were the last words of the Fire Lord as he became motionless. The trio stood staring at the corpse of the dead man, and they hugged each other as tightly as they could. At last, the whole planet would once again be free! Aang had fulfilled his destiny, and the Fire Nation had lost it's power.

Before they started to speak, the great door was blasted open with a huge ball of fire! A boy stood before them with several other fire benders who were dressed in a very different manner.

The Avatar! Get him!

Katara,Toph,you guys take care of the Fire Benders. I will deal with their leader, his face tells me that he want to challenge me badly...

Good luck Aang

Yeah, kick that guy's butt twinkle-toes!

The battle lasted for several minutes, and the trio was in big trouble. Due to the battle with Ozai, they were tired out, and the Fire Benders and their leader were stronger than they expected. Even the weakest looking Fire Bender was able to fight at the level of a master, some bending lightning and others shooting fireballs which were stronger than even Ozai's Fire Bending. Soon enough, the trio was separated into several rooms after chasing and running around the palace. The freedom fighters outside the palace were not aware of anything happening inside and knew that only The Avatar was to defeat the Fire Lord.

Aang fought the leader of the group and a dark skinned Fire Bender in a room far away from the others. He fought ferociously, knowing that this battle was not to be lost. But in his heart, he knew that he was indeed losing to complete strangers, and if he lost, the whole mission would fail.

Suddenly, In the midst of the battle, Katara appeared at the doorway. She had tears in her eyes, and she indicated to stop.

We surrender! Just don't…..

Katara! What are you doing!? We can't surrender! The whole world is counting on us!

But Aang! I….I had no…..

The conversation left Aang careless, and the leader of the group hammered Aang's head with his metal bracelets. As Aang passed out, he saw the blurred vision of a bloody Toph being carried away…….