Reading through the Millenium Fortress thread, I saw a post about how to gen a world completely empty of civilised races, except for your own fort.
- Access your raws, and set the max age for dwarves as 4. This way, they will die before they breed, and your dwarves will die during worldgen.
- Generate a world, allowing 1 civ and requiring a player civ. You will have a few errors until it manages to place a dwarf civ, which will promptly die of old age around year 2 or 3.
- Open the raws for that world, and change the lifespan of dwarves back to normal.
You now have a world with no civilizations, no liaison, no caravans, no invaders. Luckily, fort creation is magic, and the game will generate 7 dwarves from thin air, and an additional 2 waves of migrants that are generated on the spot. After that, nothing. Those two migrant waves seem to always be 8-9 dwarves, so you'll have 15-16 dwarves at the end of year 1.
It sounded like a fun idea, so I tried it. The results were... not quite what I expected.
I dropped maxage to a setting of 1:2 and got going. Worldgen blazed through 500 years of history in less than a second. So far, so good. However, legends mode revealed a 500 year old dynastic empire - a dwarven civilisation calling itself "The Muscular Ring", entirely made up of warrior toddlers.
Unsurprisingly, a lot of dwarves did die of old age after lives completely blank of any events, but rather worryingly, these one year olds were somehow managing to breed. There were plenty of long running families that did manage to survive for several generations. Alongside these, a lot of dwarfs started appearing out of nowhere, listed as being "of unknown parentage", which I assume is gamespeak for being popped into existence because the population was too low.
Marrying and having children wasn't the only adult feature of these one year olds. The Muscular Ring managed to rack up an impressive list of enemies, having regularly gone to war with trolls and megabeasts, despite most of their warriors being less than three months old.
Since special rules seemed to be in place preventing extinction of the dwarves during worldgen, I decided to give it a try in fortress mode.
Fortress mode with max age of 2 is very, very bizarre.
The initial 7 dwarves and most migrants seem to have no age check for reaching adulthood - it is simply assumed that they are adults from the start - it is therefore possible to get some work done. One exception to this is migrant children. The migration system apparently decides at random that some migrants should be children, and so assigns them an age in the range between baby age and child age.... totally ignoring the max age. As soon as these children enter the map, they are checked against maxage, and die instantly.
The most amusing feature of this game is that the max age checks always happen on new years day. Once a year, at exactly the same instant, half the fortress population drop dead. Since part of my experiment was in trying to see whether one year old adults could marry and breed, I'd packed everybody into a tiny statue hall to socialise... The fort has regular, scheduled and predictable tantrum spirals.
Those dwarves that did manage to marry and have children... weren't helping matters. Offscreen migrants kept coming, keeping the fort alive for long enough for some marriages and births to happen. The born dwarves are not assumed to be adults from the start. Despite being a lot older than some of the migrants, they are treated as babies.... babies who will outlive their parents and die of old age without ever growing to become a child. After a few years, one third of the fort population was orphan baby elders, being looked after by the younger "adult" migrants, constantly crawling around on the edge death by hunger or thirst, and having to be brought food.
During fortress mode, the outside world is completely immune to aging. The king of The Muscular Ring has been reigning now for four years, and the liason has visited four times, without seeming to die of old age. This is good, as the only way to keep the fort alive is by attracting migrants, so every year when the traders came, the dwarves make a huge offering of crafts, hoping to offset the effects of so many deaths, hoping that the gifts arrive in time that new workers arrive before the annual new year riot.
I'm going to keep playing until the fortress dies. Maybe when this fort falls, the world will truly be empty.