Comment if you have any ideas.
These are my ideas:
You could burn down wooden structures like wooden walls, doors, window frames, spikes, high external walls etc.
You could use a torch or some other type of flammable object.
When you hit a wall with a torch for example it would have a 1/50 chance to light it on fire. (It would only be able to hit the wall 5 times or less before it breaks to stop fresh spawns from burning the whole map)
Incendiary rocket could be higher like 1/3.
Having camp fires or furnaces in a wooden base could light it on fire, so you’d need a type of fire extinguisher which you could find at the monuments.
Stone or metal would be inflammable.
Maybe water buckets which you could fill up from a lake or the rain collector.
During rain all buildings on fire would go out.
Fire would slowly damage an object until it breaks.
Torches could become more expensive or the chance of a building catching on fire when you hit it with a torch could be 1/100.
Some sort of sprinkler which you could fill up with water using a water bucket and it protects a 3x3 area (or more).