After the Frontier war against the IMC, the Militia has now finally won what thought to be a endless war and now the galaxy will live in peace. The Militia transformed into a new government and military force for the galaxy called "The Alliance" and with the help of their Titans, they can rebuild that was lost and bring a new age of humanity to all of the galaxy. Unfortunately peace will not last as a more powerful and destruction empire came out of the shadows with new mechs known as Knightmare which was created by The Holy Britannian Empire lead by Charles Zi Britannia who wants to rule Earth and soon the galaxy with his army and wipe out anyone who stands against him and his new empire. Disbite the Alliance were strong and powerful with their Titans, they stand no chance and as the result of it they have to evacuate Earth and made Mars as the Alliance's main base as they rebuild their forces. Due to many pilots were lost during Britannians first strike, they have to recruit young man and women who have lost their parents by Britannian and train them to be the next generations of pilots. One od these Pilots is named Y/n L/n who lost his parents, friends and his home became of Britannian and he seeks revenge on them and trained his whole life to take down Britannian and their empire once for all. Years later he will get his chance when they return to Earth in hopes to battle Britannian once again and make a base within the planet so they can have a fighting chance however Y/n must face challenges while returning to planet Earth but with his Titan partner, his team and his friends, he'll overcome anything he can and will retake Earth and make Britannian pay.