These two worlds are less parallel, but they deal with a similar problem. There are not enough resources to support the number of people.
Recession Fears:
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Near the galactic century of the Two-Step Galaxy is seed black hole that podded off from the central black hole. It was an unstable black hole, spitting out radiation bursts that could sterilize whole solar systems.
This was a good thing.
Engineers wrangled it into orbit around a cluster of a half-dozen stars. This orbit would take a mere five millenia to complete.
Taps and shields were raised. The power lines ran for over a lightyear, and the shields could if moved, cleave a sun in two.
Then the serious work began.
It took several black hole years to be completed. Civilizations rose and fell on the planets inside the circuit of the black hole. Some helped build, and others stared at the odd lights in the skies from the safety of their campfires. One of the major investor races transcended physical existence, and left the project to other races. This project absorbed the efforts of tens of millions of sentient beings from several dozen species.
And then it became operational.
It was an intergalactic jumpgate which could reach outside the local galactic cluster and reach the thriving markets in over a dozen galactic clusters.
Suddenly, those eight solar systems in the star cluster inside the orbit of the black hole became the most valuable real estate in over a thousand galaxies. To merely buy an apartment would cost the income of a major stellar power for a year.
The Major Investor Races made so much money they could have ....and they did.
But time passes.
In this case, about a half-million years. The Ancient Engineers had built very well. But eventually, even atoms sometimes fade. An electron here, one there just dissappears. It was nothing so simple as metals merging over millenia as Brownian motion danced the heavy metal song, nor as cosmic rays plastered the sides of the great shields because those had been rerouted in a collossal feat of engineering that covered tens of thousands of lightyears in an energy shield/sponge.
It began to glitch once in a while.
Other, newer port cities opened up, and soon enough they improved themselves to have longer range.
And so the port fell into disuse, and people eventually forgot it was here.
It was tiredness that did in the Pan-Galactic Fantasia more than anything else. In order to run a civilization stretching across ten thousand galaxies you have to be endless inquisitive to learn, and famously tolerant, and full of integrity and honor. And not only you, but a huge percentage of everyone has to be like that, or striving very hard to be like that.
Its enormously tiring. Barbarism was simply less work.
It 'helped' that a number of Senior Races chose to transcend at the same time.
And so things fell apart over a hundred thousand years, and in the end the War came, and with it the Great Dark. Barbarians on the outside had long lusted for the Fantasia's wealth. Add in the ill chance of several galaxies held by barbarian species about to run into antimatter galaxies and become uninhabitable. Add in the fact that the Fantasia was weak and stumbling.
It was not quite as inevitable as 2+2=4.
Galaxies were flung against galaxies. Suns going nova and planet spaces full of four hundred billion sentients being vaped was not even worthy of more than the local news it was such a small disaster.
The Two-step Galaxy was far from the center of things, and deep behind the frontier so it was spared direct conflict. Of course, it suffered horribly as the economy crashed so hard and so fast that trillions of people had to be tossed into cryosleep to save them.
More time passed, and the barbarians have largely won although there are a few 'civilized' galaxies here and there for the barbarian tide has ebbed, and the proud warrirors and wreckers have spent themselves to thinness.
And then a new civilization arose on a very old world. Its people know little of this, only that in their ruins are many incomprensible and unrelated items. They have lost their history, and do not know that their kind used to bend stars to their will, and leap galaxies for a jest. This world is one of the Port Worlds in the center of the Black Hole Orbit.
They travelled to the Black Hole in their primitive FTL ships, and found the Port. They also found tens of millions of cryos of a thousand races.
They do not understand the Port, and they don't have the means to run it.
So they began waking people, but they did it wrong. Much more woke than they realized. And unfortunately, these are refugees. These are not the trained engineers they sought. And there is little food.
Can the forty person crew of the History Diver organize a million aliens of ten species who don't really know what they're doing, but might have a vague idea into a work force. If not, the refugees will follow their ship back home, and wreck the Diver's world with their demands backed up by some alien tech and skills they have.
And if the Diver crew wants to use the Port, they need these people. Because a million workers is not enough, not really. In order to really run right, there needs to be another four million workers.
But the wakened workers have shown the diver crew how to 'dream speak' to the sleepers in the cryo cases. And most of the sleepers don't want to awaken.
Can the Diver crew turn its consumers into producers who solve more problems than they create. They've got a few days, maybe a couple weeks, and then things will likely become very bad.
Happily, a verser came along with them on their interstellar flight. This flight was the farthest, by far, this civ has gone. And now they realize they can open up the universe, and rebuild.
Of course, there are barbarian society around the area which would love to run in and grab slaves.
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Maybe I'll do the other world later.
