TL;DRKinda like supply challenge, except it would only be one material that you would constantly have to gather and just in bigger and bigger quantity. Forcing you to make bigger and bigger supply of the demand.
What ?Simply it would be some kinda of a 'feed the beast'. You have some mouth or a box that you have to keep feeding material into, and it will have time interval, and constantly increasing. Maybe that supply will be limited to x amount of input at your starting location. So you will have to explore for another input location to feed it more over there, and then explore to another location. Constantly forcing you to explore and fight your way to clear aliens.
So you could simply create a normal game, whatever difficulty you want, and just tick a 'feed the beast mode', and a box or a special place will spawn on your starting location, that you will have to provide material into. That 'beast' would then grow as you feed it and then it would require more and more. I'm not sure if it would need to look like a beast, could be a box. But you get the point, it grows and you have to keep it calm from killing you.
Why ?I simply stop wanting to play the game after I reached specific point, cause I just don't see any point. Shooting a rocket just seems to dull and making the game end.
I want something to kill me and I want to run of the tracks. Causing this mode to end the game if I can't feed it anymore. Eventually it would end, but it would most likely make you have to use all your talents in order to build a huge base to feed it as much as you can, and you would be able to beat your record. And you could even add some way, that if you reach specific point, that would just be insane to get, you would win the game. But then maybe that would have a time record on it. And you could also increase the difficulty of the interval, making it harder. Making it actually maybe fun for people to watch streamers playing this game. Making them sweat playing the game.