OH SHIT I KNOW THIS ONE!
That "Derelict" is a superweapon made by the humans on the eve of their destruction. And it is a legit superweapon - equipped with a 100% sophont machine intelligence that is able to out-think and out-gun the Compact at every turn. It took on something like five of their flagships along with their attendant fleets at the same time, and barely won that fight. The only reason the humans lost was because the Compact sent an EVEN LARGER fleet straight to Earth.
The funny thing is that the Humans were actually even more advanced than the Compact. When the Compact came along, the Humans immediately saw them for what they were and politely declined... and then the Compact came back with the good old "I wasn't asking" shtick, and then it became a war of one small group with better tech vs a far larger group with absurd numbers on their side.
The few remaining humans are the result of a sleeper ship showing up and colonizing a virgin world, only for the Compact to discover and conquer them a few hundred years later. All knowledge of Earth and their origins are expunged, but the Compact itself is very much aware of their past dealings with the Humans.
And in the meantime, this one Superweapon has been lurking in the galaxy, her crew long dead from that last climactic battle, rightfully angry and seething about the Compact, and wreaking a horrible and bloody revenge against the conquerors of humanity.
And then she's boarded by this group of human cadets while sleeping and the whole ballgame changes.
The funny thing is that the Humans were actually even more advanced than the Compact. When the Compact came along, the Humans immediately saw them for what they were and politely declined... and then the Compact came back with the good old "I wasn't asking" shtick, and then it became a war of one small group with better tech vs a far larger group with absurd numbers on their side.
The few remaining humans are the result of a sleeper ship showing up and colonizing a virgin world, only for the Compact to discover and conquer them a few hundred years later. All knowledge of Earth and their origins are expunged, but the Compact itself is very much aware of their past dealings with the Humans.
And in the meantime, this one Superweapon has been lurking in the galaxy, her crew long dead from that last climactic battle, rightfully angry and seething about the Compact, and wreaking a horrible and bloody revenge against the conquerors of humanity.
And then she's boarded by this group of human cadets while sleeping and the whole ballgame changes.