Are BSF and Tyranids somehow connected to each other? Is it implied somewhere? I recently learned about the seventh Blackstone Fortress and its supposedly alien origins, alien maybe even to the Milky Way galaxy. Tyranids are known to have come from the outer space, supposedly from the other galaxy. Do BSF somehow interact with Tyranids? Can Tyranids be defeated by the usage of BSF? Were the Tyranids originally the species who created the BSF and later somehow degradated to the state as we know them now (yeah, I know, visited Milky Way, made seven superstructures and fled to the other galaxies)? Too many questions, is the interaction between BSF and Tyranids mentioned somewhere in the lore?