Nah, lemme just…
We gotta go four the triple-pronged approach here.
Masses of atlanteans smashed together create some grotesque drakes (flightless dragons, for those unaware) that become exceedingly hard to kill because they’re multiple organisms, like a Man O’ War.
We can then talk about atlantean-corrupted dragons… But the first idea I had was corrupted sea serpents that would fire sprays of tainted seawater from their mouths? Could be interesting to essentially have an active threat that poisons people and makes actual sea travel more dangerous.
I’ll see if I come up with anything else…