Depends on if it's been Daemon-ified or not, is my guess. If Daemons: fuck that shit we're out
If no Daemon World: Hopefully Tzeentch finds this funny enough to make one of our cult leaders a Champion?
I tried to see if there's any fluff about nids and chaos worlds, and there is one - but it seems the nids only invaded it because they thought it was an imperial world full of biomass. They were half right, because it was an imperial world full of biomass with a gigantic chaos fortress buried underneath
Nids didn't have funLooks like they can fight chaos and win, it's just that they get absolutely no biomass out of a lot of effort, so like cron worlds they just go around them because there's not much point. It would be cool if the Doom of Malan'tai taught the rest of the nids how to harvest souls/warpstuff for power, so they wouldn't have a biomass energy crisis anymore
Actually thinking on it further, it's a shame the Doom isn't developed on. You have the first tyranid organism capable of feeding on souls instead of biomass, that then eats an entire eldar craftworld... Then it just disappears? What is the giant nerd up to? We'll never know. Hive fleet Doom will never see the light of day :[
I think that they are sent out from the Hive Fleets, but I don't think it's fleeing, and I believe LW is right as to the psychic thing, but I feel like them having a fair amount of free will, rather than just being psychic slaves, fits in. Also helps them fit in.
I don't think it's free will, just more autonomy, because they lack the ability to rebel against the hive. Effectively all tyranid creatures follow protocols set out by the hive mind, and then default to biological instincts if they are out of synapse. The exceptions to this are the commanders, the lictors and genestealers. Those three are given commands which they must fulfill, but are allowed to independently form the protocols they think would achieve those objectives
As for Tau: Don't forget Nagi. Reading/probing minds is great for screening people, and it takes a brain-infiltrator to know a brain-infiltrator.
Traumatic
Ork genestealer cults are certainly a thing, but I don't know how successful they are or aren't. The two bioweapons of 40k always seem to have a back-and-forth. Orks spring from nothing infinitely, seemingly, while Tyranids come in infinite numbers from out of nowhere.
I think genestealer ork hybrids wouldn't work because they can't subterfuge their way to the top of Ork society; they have to krump the biggest and toughest ork around. Which is a problem, because there's no such thing as a weak ork warboss, and given how orks regularly share space hulks with genestealers, means genestealers aren't very good at not getting krumped
Yeah but Tyranids are the monolithic tide washing across the galaxy whose intelligence cares nothing for the passage of time. They don't have deadlines, mortality or battle plans to worry about. So drifting through space for a few millennia to get where they need to go is fine for them. If they get bored they can just shove a few thousand organisms into the bio-pits and whittle away the years making new and funky organisms.
They are fleeing something in their own galaxy and they are running in the whole tragedy of the commons where they have to keep finding new biomass, so they're not exactly like crons or chaos which have near indefinite shelf lives