Here's the intel I was able to intercept from Pelagos' communications with his current sponsor:
- Underwater ruins have been found dotting the Pacific ocean.
- Most of them date anywhere from 12,000 B.C. to 6,000 B.C., but it's not clear what method of dating is being used here.
- The architectural style is unknown but shows proto-Japanese and proto-Mayan characteristics.
- Signs of radioactive elements (such as uranium) have been found in clearly artificial containers, suggesting that the builders found a use for them in the same fashion as the Baghdad Battery.
- Carvings in an unknown language were found and are being deciphered. There is no translation key available yet, so this process is expected to take several years.
Most of Wavelength's speculation about an active civilization concerns Pelagos' requests for a massive quantity of underwater explosives, deep sonar, and messages (so far unavailable to the villain community) sent to the Pentagon. Of course they concluded that this means that he's at war with some sort of underwater civilization, and not (for example) doing blasting that he's concerned will be picked up by Navy sonar installations and misinterpreted.
No current geological theory allows for a sunken continent in that time range, and no existing - and credible - theory of parabiology allows for a whole civilization of water-adapted superhumans during that time either.
What we know of Sea-czar and the Deep One is that they are interfering with Pelagos' operations. How, and why, are answers they haven't deigned to share with anyone who talks to me.
This information has a place in this guide for two reasons. First, to illustrate the interesting things that a villain can run into, even in an unexpected place like the Pacific Ocean. Second, to remind young villains to always look for opportunity. Both of Pelagos' underwater rivals have found some advantage they can gain by messing with him. Once I get more details on their caper, I'll share what I can for educational purposes, but for now, just remember - if your hero is doing something unusual, it's almost never because he is bored or something. Heroes can have capers too, so find out more about his, and try to take advantage of it.