I like to know what you think about that. An ex. Orks and IG
I've read at multiple sources that one of the reasons nids try not to fight against crons is because the special metal their bodies are made of cannot be absorbed by nids.Tyranids and Necrons? Kind of fluffy too - the Necrons want souls, Tyranids biomass. After they wipe everyone else out, the Tyranids could try adding Necron metal to the next generation before moving to another galaxy.