Let's talk aliens.

[sovereign]

Biological weapons would be able to, at most, destroy a single ship and possibly other ships in very close physical proximity (anything in range of its "feelers"). The piece of the consciousness controlling that ship would be hit by it, but not killed- death of a controlled ship does affect the Nomads, but not a whole lot. Such weapons, regardless of origin, would do the same thing as shooting the ships with guns would do- kill the vessel.

To target the collective, you'd need to either A) target their power supply like opening the hypergate did, or B) target the telepathic network itself. The latter option would require humans with telepathic abilities or machines duplicating that- as well as intimate knowledge of how the Nomads talk to each other. If you could build machines that "talked" the same way Nomads did, you could theoretically DDoS the Mindshare, keeping them from communicating and either driving the minds insane or at least immobilizing the physical manifestations (meaning that a group of strike teams could clean house fairly effectively). Theoretically. If you didn't keep it secretive enough, they might find a way to resist it or do something similar to modulating a comm frequency- "dodging" your interference. You'd need to catch them by surprise, and with enough machines to knock out the network in one fell swoop. That's the sort of thing you should be looking at for this.

It's entirely possible that the Nomads have already foreseen such a "weakness" and have already set up protocols to deal with it and thus avoid another disaster like the Battle of Omicron Major. But if you wanted to "capture" a Nomad ship, this would be where you should start looking- using telepathic abilities similar to the Nomads to "blot out" a small area from the network as well as keeping the mental imprint running the ship occupied instead of self-destructing. I have a theory on how you might "assassinate" a given personality, but that's not for display until I've thought about it more- and there's no way humans could figure it out with their current level of understanding.

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