Game Idea : Fallout - Lake City
Location : Chicago
Year : 2300
Idea : You wake up from your deep slumber inside one of Enclave's clone pods. you've been created inside an AI controlled enclave cloning station called Eden Facility, the last stronghold of the Enclave since the annihilation of the Enclave forces at Washington. the enclave is deeply divided between following it's previous ideology or adapting to the situation and opening it's gates to the rest of the wasteland.
The ruins of Chicago is currently a warzone between the Brotherhood and the Reavers. a new NCR-like faction is also making it's way to south from Canada, at first you can find their scouts (mountain rangers) scouting the ruins and wandering the wilds, as the game progresses their presence becomes more noticable. the legion is also on the march to expand it's influence from the south-west, having faced a broken and divided Brotherhood of Mid-west on their way they have easily captured and integrated intelligent super-mutants and ghouls into their ranks as slaves.
It is up to the player to choose the fate of Chicago, You can attempt to hold dialogue with each faction or subdue/destroy them. after a set amount of time you have to face the might of the legion with your allies' help. if you have failed to prepare Chicago for the final throwdown the city will be conquered by the Legion, most of the inhabitants will be slaughtered or enslaved and only a few remote settlements will remain on the map to offer you services. you can also choose to join the legion, and help them capture and enslave Chicago one settlement at a time.
as the game progresses however, you delve deeper into the mysterious AI that controls Eden and find the true purpose of your creation. and will have to choose to aid Eden or end the AI.
Locations :
Marilyn temple
A temple build near the statue of a diety known as Merilyn. legends has it that the first followers of the temple were just settlers who lived around a broken statue of a woman. until one day they woke up and found the giant, restored statue of Marilyn in the middle of their settlement. unbeknownst to them the statue is actually an offline Liberty Prime built by the Enclave and concealed within a crudely built Marilyn Monroe statue to be used as a weapon in-case the Brotherhood became a danger to their existence, the plan turned out to be unneeded as the Brotherhood started to decay from within. player has the choice to delve deep into the sewer system underneath the statue and activate it to wipe out the settlement, or put it on standby to later use against the Legion.
China-town : A small settlement inside Chicago. similar to San Francisco it has a chinese theme to it, the settlement is controlled by gangs who control the drug trade and offer mercenary services to other settlements, you can find some exotic gear/weapons there.
Enclave Station Eden : a concealed cloning facility underneath lake michigan. you start the game from here and after a series of tutorials you are flown to the mainland to the nearest enclave outpost, things go hairy from there and you lose contact with the Enclave. you then start to roam the map on your own. you can try to find your squadmates or abandon the mission to travel around Chicago.

Maybe I'll add more maybe I don't. but yeah I think it's about time we see a snowy terrain in Fallout.
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Choose Background : While you were inside the cloning chamber you were living inside a simulated enviroment. you can choose what sort of life you were having inside that pod, based on your past life you will gain some bonuses to your stats or perks. serves to provide you with a pre-selected character attributes.
for example if you were living the life of a doctor your character is built with high intelligence and has perks that deal with stimpacks and chems. ofc you can still create your character the old-fashioned way.
also you get to choose your age, the more aged your character is the more perks/stats you can choose from start. (up to a certain specified maximum so that you cant abuse it.)