D&D General How Have Eclipses Been Used in your D&D?

[Paul Farquhar]

But why? Why does a fantasy realm with magic actually need orbital mechanics? (I'm not a flat earther!) But why couldn't the realm be flat

Then you need to come up with some other explanation as to why eclipses occur. And you need to take into account established setting details, such as the number and nature of moons. Eberron has 13, Faerun has two, plus some asteroids, etc. One moon, with an apparent size the same as the sun, is a far from standard arrangement.

There are advantages of different arrangements. If the apparent size of a moon is very much larger than the sun, or more dramatically, the world is itself a moon of a giant planet, then you would have very much longer periods of darkness, when all sorts of stuff could happen.

Another real world detail that could be used in D&D: you get abnormally high tides in conjunction with the eclipse. A good time for an unpronounceable fishman invasion.