In my story, there are a large group of technologically backwards Earthmen who wish to remove a futuristic Martian arcology from their ancestral land. The Earthmen do not have any 20th or 21st century technology, and using fossil fuels is strictly forbidden. The large gap in technology levels means that they would likely lose any war or battle without the element of surprise, so they would like the Martians to not realise what they're doing until it's too late to stop it. As long as the Martians don't see a glaringly obvious threat, the Earthmen are able to take decades or even a century to prepare if necessary.
How should these Earthmen go about knocking down that huge futuristic building? Could it be done with only very primitive technology, or would steel tools or an engine or two really help? Is there some chemical or technological wonder they need to steal from the Martians first?
To get you started, here's an incomplete list of things I imagine approximately bronze age people could weaponise:
- Undermining and somehow interfering with the foundations
- Undermining and somehow causing a landslide or sinkhole
- Battering ram seige engine
- Cultivating the forest near the arcology to become more or less flammable is a possibility, but not right up against the walls of the arcology as the area close around it is at least somewhat controlled by the Martians
- Diverted river
- Sabotaging some kind of factory inside the arcology (many things are manufactured in there)
Edited to add further info: The design of the arcology is negotiable for story convenience; this story isn't finished and it isn't a sequel. But if you have no particular requirements to make your answer work, imagine this: The arcology is a huge cube. Skyscraper tall. Lower floor walls could be reinforced concrete. Upper floor outer walls are not tough, could be glass. Load bearing structures could be made from exotic engineered materials like nanotubes or high tech composites or whatever, engineered to optimise vertical weight bearing specifically and might not be as resistant to attacks from the side as reinforced concrete.
You absolutely cannot climb up the side without being spotted.
Earthmen can go inside, but they'll be chased out if they're found being naughty. They are not in a state of war before the arcology is attacked.
The Martians have nothing as magical as anti-gravity. They're not actually very far advanced past real world 21st century Earth technology. Their spaceships are just normal rockets. They like to put a whole city in one big building instead of lots of little ones, that's the arcology (I realise that it makes little sense to build like that in real life, but man it would look cool).
Yes, filling it with poison gas or bees would be sufficient. Making one side of the structure collapse would be OK if that's the best we can do.
Like the Psychlos in Battlefield Earth, these Martians are arrogant bastards and may overlook the Earthmen's schemes if it's not obvious what's happening, because they have a comically low opinion of the Earthmen's intelligence.