Some of the fights are basically arena fights. These types of 1vs1 missions would become their own thing, a side thing to earn money and weapons.
Some of the missions have really cool build-ups, like this one with a supercomputer made before the war that might have backup data of dangerous/forbidden technology so it has to be destroyed.
Some of the minor factions are funded by corporations, for example, this nazi terrorist group receives financial aid from a Japanese corp that develops biotechnology. Why would a corporation do this? you need pawns to win a war.
Eventually, you the player become your own piece, no longer tied to bullshit politics. So... the corporation you helped archive pax corporis ends up investing in killing you.
You get invited to Raven HQ to defuse a bomb but it's actually a trap to kill you, The chess master behind the scenes is actually an AI made before the war to keep humanity in check. You kill this god of mankind and free humanity to make their own choices again.
So the next entry is basically dog shit.
Your main antagonist is this cuck called Stinger, who refers to himself in 3rd person. He's a boring antagonist.
They also introduced your waifu AC pilot that uses a pink AC
Eventually, you fight Stinger and in his last attempt to get the upper hand, he steals a prototype weapon called Phantasma, made by a terrorist organization.
The fight is kinda bullshit but not super hard... (Ibis cel 240...), he dies like a bitch and it was not really a memorable fight.
And this is how it ends. Pretty lame... but introduces elements that get refined in Master of the Arena, like arena fights and they develop more the rival/antagonist themes that future games utilize.
Here it's a more grounded story, a revenge plot with some twists! Your parents get killed by Hustler One the legendary AC pilot that not only he's the best but also the champion of the arena. You become a raven with the sole purpose to get the chance to kill this asshole and avenge your parents.
Eventually, you git gud and fight Hustler one and destroyed his ass. Yet he is still the top AC of the arena... odd.
Yes is the fucking ai from the first game. It's top of his game cause every pilot that gits gud gets deleted by the ai cause you become a threat to his bullshit perfect world calculations. You fight two Nine ballers at the same time then the upgraded version.
That's how the story ends. The Arena and Raven Nest become offline after the fight. In my headcanon, it's because both endings happen in parallel to each other.