Artifact:

Südlicher König Cross:

Actually there's a fungus that does pretty much the same to some ants...so yes it is possible.

 

Wait what? lol im confused

There is a fungus that takes over ants, and thats it, there is noting like the flood anywhere, something that can infect anything living, reproduce from it, and become smarter. The fungus you speak of has a natural enemy that can kill it, the flood doesnt, thats why its soo questionable

still, the flood was designed after that fungus, which controls the ant to higher points, by the time the ant gets there, it is decomposed and dies, the spores of the fungus can now travel to infect other ants and keeping the cycle up, just add the fact of a "Gavemind and a Hive" and you got the flood.