So this requires a few things, First off, single organisms can have pretty advanced local processing of control. An octopus has a nerve cluster for each tentac

So this requires a few things, First off, single organisms can have pretty advanced local processing of control. An octopus has a nerve cluster for each tentacle that can operate independently of the main brain [1]. So in at least one case, biological brains delegate work out to another region of the body. An argonaut octopus actually detaches part of it body, which as far as i can tell, keeps living for a while. it's kind of creepy. The only thing i can't find an example of, is remote control. A detachable body part, with a nerve cluster, that responds to light or sound seems like what would be needed for the base creature. Evolution hasn't stumbled on that trifecta here on earth. But it sure seems like something that could have come about. The latency argument isn't compelling. If i can send one message, i can send another hundred billion messages along with it. So, sure only a few thousand round trips, but a fabulous amount of information transferred. There's no actual biological equivalent to a semi autonomous drone, so i'm not sure what that would look like before the creature took to the stars. There's also no real obvious way for this lone detatched tentacle to consume the resources of a planet. But whatever. I think one entity with those three features might have a chance. Also, is the creature smart? Does it get to genetically engineer itself? do cyborgs count? That greatly simplifies things as well. The detachable parts could have detachable parts, and recurse down to whatever arbitrary degree is useful. Alternatively if you admit superorganisms, then everything is much easier. So anyway, you don't really need to send many messages when the message is "here are the latest designs for industrial architecture to dismantle a solar system and send the resources back" It's up to the billions of lone tenticles and their machines to execute the will of the super brain. On the other hand, yeah, there's not going to be a galaxy sized amoeba or panther or anything like that. maybe an incredibly fine mist of fungus or mold, but i think it'd be too hard to keep a system like that from collapsing in on itself from too much mass. a galaxy sized ring of spider silk orbiting a black hole sounds like great science fiction. but i can't imagine that working. [1] https://en.wikipedia.org/wiki/Octopus#Nervous_system_and_senses https://en.wikipedia.org/wiki/Octopus#Nervous_system_and_sen... [2] https://en.wikipedia.org/wiki/Argonaut_(animal)#Sexual_dimorphism_and_reproduction https://en.wikipedia.org/wiki/Argonaut_(animal)#Sexual_dimor... [3] https://en.wikipedia.org/wiki/Superorganism https://en.wikipedia.org/wiki/Superorganism