The Culture explores 40K II: Now With 100% more Fanfiction

[Gavinfoxx]

So is there any plausible way other than 'suffering of sapient creatures' that could prevent the Dark Eldar from all wasting away?

And I think blank-bomb is just banishment rather than annihilation. Similar to it's inverse, a psych-bomb to create turbulence in the warp.

The Hydra plan might work. You WOULD have to do that (or something like it) if you want to stop similar but slightly different entities from reforming. Parts of it could be changed to be technological, but you would need the simultaneous unification of thought across all sapients in the galaxy to do the killing blow, though. And then a period of unified thought to make sure things stay dead.

Alternately, making pretty much every bio-sapient in the galaxy a dull soul or a blank might do something, along with those necron thingies set to 'calm the warp'. That might starve some types of things. You'd also have to do this to every non-sapient with more than a minor psychic presence (there are nonsapient psyker species).

Starving the things in the warp might not kill them. It might force them to consolidate their essences in the warp, and thus make them vulnerable. Then you could go into the warp and beat them up the old fashioned way... assuming you have something that CAN destroy these (now weakened) entities...