I know pirates are hardcoded, but in two of my recent games, the seas seem to be awash with them. For a time I didn't think they ever blockaded anyone but me, but I did notice them (very occasionally) blockading AI factions.
What's unusual is the sheer number of them, in my Kyrenaian game they've cleared the seas of every other navy, I don't even dare put to sea myself any more.
I also saw some pirates on land, a half-stack of "Listerion" rebel troops who must have come ashore from a ship. Never seen that before.
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