Bury some trinkets in out-of-the-way places, then dig them up a thousand years later and sell them as antiques.
One long term project that would be useful is the slow shift of a planetary body by way of gravity "tug boating."
In a fantasy world, perhaps a dragon sleeps for 1000 years and while it slumber kobolds mind its continuously growing scales.
How so?That sort of falls into the astronomical event category.
Depends on the size of the tug boat.That's the sort of thing that you'd schedule a million years for moving a planet.
Doing that in a society like ours would fiendish. You wouldn’t need to be a scientist to detect the changing salinity, nor the changing and devastated populations of marine life. But the odds of ever identifying the source are minuscule beyond belief. You could likely pin down which ocean it’s in - the one that gets less saline. But narrowing it down enough? Nah.It started out as an online joke but you could do it as a real plot: Open a decantur of endless water under an ocean and have it slowly flood the world over a few thousand years.
Some things in RPGs are often very long-lived. What sort of very-long-term plans and efforts might they have?
Doing that in a society like ours would fiendish. You wouldn’t need to be a scientist to detect the changing salinity, nor the changing and devastated populations of marine life. But the odds of ever identifying the source are minuscule beyond belief. You could likely pin down which ocean it’s in - the one that gets less saline. But narrowing it down enough? Nah.