Many of the rules relate to skill requirements, these of which are highlighted below skill rules.
Game length is normal or long depends on how you like to play. I find longer game is easier as you have much more time for certain challenges, however sometimes it feels almost too easy. I recommend using MC Command Center to set the lifespans to somewhere in the middle of the default lifespan for normal and long.
Your sim must be an Alien (or other occult sim if you can make it work)
Your alien must be a teenager and the only sim in the household.
You must start of in any empty lot. Once you choose your lot, open the ctrl+shift+c prompt and use the cheat “money 0” to begin the challenge with precisely 0 simoleons.
You cannot move lot throughout the challenge, but you CAN import houses from the gallery and such to place on your home lot!
Your alien sim must always be disguised when going outside. If any sim looks at or socialises with your undisguised alien sim, then you have two choices for what to do with this sim.
Erase the poor sims memory
OR
Kill the witness in anyway you can :) be creative.
The choice between A and B is completely up to you. I choose to play that any sim that isn't a friend gets killed, however if the witness is more than an acquaintance (ie. a friend), then I simply erase their memory.
Once you reach the good friends status with a sim, you may take off the disguise when you are around them. However, maintain this good friends status as if they drop down from this status, the sim may no longer support your alien ways, and expose the truth.
If a friend sim has dropped down from good friends status for too long once you have shown your alien’s true form, they must be eliminated, not memory erased as they have known about the truth for too long, and will not have an effect.
Before your sim can travel anywhere outside of your hometown, you must purchase a bus pass for 150 simoleons. This also means that any sim that invited you to meet them somewhere in another town, you cannot go without this bus pass, unless the sim is asking you on a date, in which you can presume your alien sim is receiving a lift to the location.
Your alien sim came to earth with only one set of clothing (the same outfit for each category minus minor changes ie. a hat in winter). You'll need to spend 150 simoleons to get some more (one time spend to change ALL outfits).
The only furniture you may have on your home lot is outdoor furniture or portable furniture. For example, you may purchase an outdoor bench for your sim to sleep on, but not a bed.
All portable furniture (e.g. tents and sleeping bags) from the Outdoor Retreat pack are allowed and are highly recommended.
This means that no plumbing or electronic items (or any non-outdoor or unportable furniture) are permitted before having a structure to put them in. Grills and cooler boxes are permitted as well as the portable shower from Outdoor Retreat. I recommend visiting food stands for food and visiting gyms to use the shower.
Before you can build anything on your home lot, you must “purchase a building permit” for 500 simoleons. You can do this by doing Ctrl + shift+ c to open up the cheat prompt, then type money [simoleons]. For example, if my household had 540 simoleons and i wanted to buy the building permit i would type money 40 to deduct 500 simoleons from my household funds.
SKILL RULES
As well as purchasing the building permit, your alien sim must reach logic and handiness level 3. Before you can build any structure on your home lot. Once the conditions have been met, you are allowed to build only ONE room. (rule 13 shows how to build more than one room).
Level 4 Handiness is required to build more than one room for your house. Before you reach level 4 handiness, your house/shack may only have 1 room to house all your furniture.
You may not socialise with any sim before you reach level 3 charisma. The purpose of this is that your alien sim will not know human mannerisms, communication skills or basic human functions. Once the alien reaches level 4 charisma skill, they can communicate with other sims as normal minus any romance interactions (see rule number 15 for further details).
Side note for this rule, some activities passively gain relationships, for example if someone joins you in a chess game. This is permitted and does not need to be avoided as the relationship gain is not based on your alien sims communication skills.
This rule doesn't apply to alien sims across your world as your alien sim will already know how to communicate with fellow aliens. This is a good way to increase your social need.
Your alien sim cannot use any romance interactions until they reach level 5 charisma, as well as having the ability to be in relationships. But not marry or get engaged until level 8 charisma.
Your teenage alien sim may not go to school, or get a part time job. In order to go to school your sim must be able to socialise with other sims through level 3 charisma (as in rule 14), as well as achieving level 3 logic and level 3 writing. This acts as basic middle school education to allow the alien sim to enroll.
In order to get a part time job as a teen, your alien must be in high school at grade C (or above), as well as reaching level 4 charisma.
If your teen ages up into a young adult without reaching grade B at highschool, then they are not allowed a job until they finish the young adult stage of life, but can get a job as normal as an adult.
(OPTIONAL AS I KNOW THIS ONE'S KINDA WEIRD AND NOT THAT IMPORTANT) your alien sim may not use any furniture in any style other than the default style and you may not use the recolour tool until you reach level 4 painting OR level 3 photography. Your alien sim doesn’t understand human styles yet.
Your alien sim can only visit one lot aside from your home per day until your alien sim reaches fitness level 4. (this doesn't include work/school). This is due to the changes in the environment and atmosphere from Sixam to Earth, making it difficult for the alien sim to adapt to the new planet.
You cannot cook food for any other sim due to fear of poisoning and lack of cooking skills. In order to be able to cook for other sims, you must achieve level 5 cooking.
To join clubs, your alien needs charisma level 3 as well as being friends with one member of the club before joining. (suggested by villiamofwindenburg on tumblr)
HOW TO WIN
Try to achieve all the goals on the spreadsheet linked at the top of this document. The objectives are focused on “becoming human” with some larger challenges with 4 different levels of difficulty (bronze, silver, gold and platinum), as well as some one-off achievements such as the ‘Home-visit’ challenge which is to travel to space in a rocket ship! Using this spreadsheet is kinda vital as i found without it the challenge can end somewhat quickly!
MESSAGE ME IF YOU HAVE ANY IDEAS FOR ADDITIONAL ACHIEVEMENTS ON THE “ACHIEVEMENTS” PAGE OF THE SPREADSHEET! (of course i’ll credit you!)
If you actually decide to do this challenge, thank you so much! I put a lot of effort into this challenge and I really hope you enjoy it. If you do, feel free to follow me on tumblr (squeamishsims.tumblr.com) where you can ask any questions you might have. Finally, if you decide to post gameplay screenshots or anything to do with this challenge, feel free to (and please do) tag me so I can view your creations and give them some love.