The Gloriana Class Battleships first appeared in the Horus Heresy books and colected vision.
Since BFG is older I suppose they still have that battlebarge concept.
In the books, there are still battlebarges but the Gloriana class are large scale command Battle Barges, around 20km each and are the biggest knowns imperial ships after the Phalanx and Furious Abyss-class vessels.
The Vengeful Spirit during the Horus Heresy and the Vengeful Spirit, flagship of Abbaddon the despoiler are in fact one and the same.
Vengeful Spirit aside, there is a second Gloriana confirmed to be around in 40k, the Conqueror.
Few days from now, my new GPU will arrive and then I can finally play this too
