Luck directly affects the change of a hero appearing. I'm not sure of the exact numbers, but it's something like 3% chance for a hero to appear each turn, +/- 1 per Luck scale. Taking Misfortune 3 makes heroes unavailable, and taking Luck 3 makes them twice as likely to appear.
However, even with Luck, you might get unlucky and not get many heroes even in a long game.
If you want to see heroes, I suggest playing with more default settings and taking Luck 3. It doesn't produce quite as reliable income as Order, so you might end upo a bit tight on money in the early game, but all the events add up very nicely in my experience. Many other players' opinions are quite different, though.
Re: Getting Heroes to appear
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