General writing practice when talking about a fictional plot is to place it in the present tense, although maybe use the story's past tense.
Story present, story past:
"After the destruction of the Colossus, the Bastion enters the Vega node and detonates, severing the jump node. The Bastion was one of the principal GTA ships in the first Great War."
Story present:
"After the destruction of the Colossus, the Bastion enters the Vega node and detonates, severing the jump node. The Bastion is one of the principal GTA ships in the first Great War."
All past:
"After the destruction of the Colossus, the Bastion entered the Vega node and detonated, severing the jump node. The Bastion was one of the principal GTA ships in the first Great War."
The first and second emphasize that FS is a fictional story (the second moreso IMHO). The last makes it sound more like a historical document. The first provides the most information, because we have a frame of reference of when the Great War is. (ie before 'now', when the Colossus died and the Bastion blew up) You could throw in a 'had been', but most people these days are lazy and just use 'was'. (Like me!

)
Edit: Just for fun...
The Terrans and Vasudans had been at war for 14 years.
The Galatea was destroyed.
The Hades is a cheap rip-off of the Lucifer
If Capella goes supernova, at least some of the populace will have evacuated.
Capella will go supernova.
Edit 2:
populae terrae et populae vasudae fuerint in bellum quarti decimi anni.
Galatea delevit.
Hades erat vilis exemplar Luciferi.
si Capella displodit, nonnullus populi deduxerit.
Capella displodiet.
Of course you could add another.
Hercules amabatur Terra cum pugnarent contra Shivas.