Rules

 This challenge was made by sixamese-simblr on Tumblr. It was originally made for Sims 2, but I'm going to try and adapt it for Sims 4 and see how it goes.

This challenge requires:

- Get to Work (required) Spa Day, Discover University, and City Living (optional)

- On Ley Line lot trait or Cheating aspiration points to get the Fertile reward trait (can also use fertility massage from Spa Day)

- Either unlocking the Satellite Dish from Get to Work via bb.showhiddenobjects or MCCC to start an alien pregnancy

Create a new empty neighborhood, with any terrain or template you think looks best as an alien planet. From there on, create six aliens to start off with:

- A birth queen, an adult woman with the romance aspiration.

- Two colony drones, adult men with the romance aspiration.

- Three caretakers, adults of any gender with the family aspiration.

-One or Two human males as breeders with the knowledge aspiration.

Build three lots to start with: a palace for the birth queen, a house for the drones and a nursery for the caretakers. From there, play every household in the game the same number of days. The task of the birth queen is to try for baby as often as possible with the colony drones. She has fertility, the On Ley Line lot trait, or has gotten the fertility massage. Every time a set of babies is born, try for baby again and move out the previous babies to the nursery. The caretakers raise the children until they turn teens, and receive $10,000 for each baby they are to care for. If the number of sims in the nursery ever grows too large, build a new nursery and move a caretaker and their adopted children into that nursery. 

Alien Teens

Once an alien turns into a teen, role a dice to randomly assign them one of the aspirations. 1: Fortune, 2: Knowledge, 3: Family, 4: Romance, 5: Popularity, 6: roll again.

This determines their caste. From there, you can choose to randomize or choose one of the "subaspirations" (Note: I am leaving out any aspiration that requires your sim becoming another occult since Sims 4 doesn't allow hybrids).  If they have any aspiration other than family, move them into a lot with teens of the same aspiration, or on an uninhabited lot if no such lot exists. 8 days before turning into a young adult, you are allowed to age them up and send the teen to university if you have that EP. 

The castes are as follows:

Romance: The Birth Queen and the colony drones

These aliens are the only ones to reproduce, the only sim that may try for baby is the birth queen with one of the drones. There may only be one birth queen at a time, but there may be many colony drones. If there are multiple adult women with a romance aspiration, all others have to wait for their turn to become birth queen until the current queen dies or becomes infertile. They may not marry or take jobs. If there is no birth queen available, you may abduct (i.e. move in) one adult male townie or npc, more on that later.

Romance Aspirations: Serial Romantic, Soulmate

Family: the caretakers

The caretakers adopt each of the birth queen’s babies. Caretaker teens stay in the nursery where they grew up, and help with the younger sims there. They may not take jobs, taking care of the young aliens is their job.

Family Aspirations: Big Happy Family, Super Parent, Successful Lineage

Knowledge: the technicians

Technicians are the most intelligent aliens. One of their most important tasks is crafting servos to help alienkind. Servos only act as live-in servants of households of Sims with their aspiration and as such may not take jobs, but Servos of family aspiration may adopt babies. Knowledge aliens may take the following jobs: Science, Doctor, Astronaut, Conservationist, Education, Engineer, Gardener, Secret Agent.

Knowledge Aspirations: Lord of the Knits, Master Maker, Academic, Computer Whiz, Nerd Brain, Renaissance Sim, Archeology Scholar, Eco Innovator, Angling Ace, Jungle Explorer, Outdoor Enthusiast, Freelance Botanist, Hope vs Order, Strangerville Mystery

Fortune: The High Council

Fortune aliens collectively form the High Council, the alien ruling body. They have the biggest houses and most lavish lifestyles. They may take the following jobs: Actor, Business, Criminal, Law, Military, Politician, Salary Person, Writer.

Fortune Aspirations: Public Enemy, Chief of Mischief, Fabulously Wealthy, Manson Baron, City Native, The Curator, Galactic Privateer, Best Selling Author, Master Actor

Popularity: the Workers.

These aliens are the common folk and don’t have any special responsibilities. They are often artists or craftspeople. Available jobs: Athlete, Detective, Critic, Culinary, Civil Designer, Entertainer, Freelancer, Painter, Slacker, Artist, Social Media, Style Influencer.

Popularity Aspirations: Friend of the Animals, Extreme Sports Enthusiast, Bodybuilder, Musical Genius, Painter Extraordinaire, Master Chef, Master Mixologist, Beach Life, Mt. Komorebi Sightseer, Friend of the World, Party Animal, World Famous Celebrity, Leader of the Pack, Joke Star

Human Sims

If there is no birth queen available, you may move in a single male townie or npc. Or, you may send a male human teen to college and graduate him as soon as there is no birth queen available. He lives in a lot of his own, and his task is to get abducted until there is a new birth queen available. He may raise the resulting babies himself, or they may be moved into the nursery with the caretakers. He does not have any fertility benefits. His children are regular members of alien society. He may not take a new job, only keep one he may already have.

Drone Exchange

Once a teen sim has aged into a YA, you have the ability to send them off to another alien colony, and get a new drone in exchange. This allows for some genetic variation.

The challenge ends when a birth queen whose birth mother was born in game dies of old age.

General mays and may nots:

- You may cheat for money whenever. That’s not the point of the challenge. I’m not your caretaker.

- Sims may marry and woohoo whomever, although Romance sims may not marry and try for baby is forbidden for anyone but the current Birth Queen.

-You may choose traits, childhood aspirations, and the "subaspiratoins" 

- You may not use risky whoohoo mods.

- You may not use the potion of youth, other ways of extending life are fine