Craftworlds vary in size but they are basically miniature planets, like world-engines. Both vary in size to a degree so some Craftworlds are bigger than some world-engines I'd imagine.Battlebarge is subset of Battleship. So it's GC->Battleship->Dreadnaught->Worldship. Dreadnaught and worldships are both basically just "Fuckoff big." The line between them is where the ship starts to have a noticeable amount of gravity. I don't think craftworlds are that big? That's more World Engine-type stuff.
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Craftworld
"A craftworld is a sentient being, with a hundred thousand minds." —High Inquisitor Czevak A craftworld is a vast, planetoid-sized spacecraft populated by the Asuryani faction of the highly advanced humanoid species known as the Aeldari. The craftworlds travel through the void of space at...