What determines the frequency of attacks on settlements?
When I was done waiting for the evening to fall to start a specific quest by sitting on a chair for six hours, I got three messages of settlements being under attack. Since I rarely see any of them being attacked during 'normal' gameplay, I started wondering what determines the frequency of the attacks?
Is it completely random, or does the chance of happening increases when you are not doing anything? Or are there other contributing factors (if so, which?)
Update: I have full defenses on all settlements and currently play on normal difficulty. One of them even has a defense of 90+ (combined water + food: 44) and is surrounded by walls. One important reason for asking this question is that I would like to prevent fast traveling. The three settlements that got attacked are located in the corners of the map, so I had no chance to helping them all without fast traveling (you fail the associated misc. quest when not responding in time). If I can do something to reduce the chances of it happening, this would reduce that problem.
Best Answer
Typically the more resources and fewer defenses you have at a given settlement, the greater chances it has of being attacked. I will post a credible source if/when I find one, but it mostly seems to be claims from players posting on various forums.
However, I believe the game does mention early on that you should try to get your defense equal to (or greater than!) the sum of food + water. (Hopefully, I'm remembering that correctly). And that makes sense that would contribute to the likelihood of attack. I definitely have Tenpines Bluff attacked much more frequently than the others (i.e. Sanctuary) since I refuse to equip it with defenses. Raiders/supermutants seem much less interested in settlements surrounded by turrets/traps/etc.
Additional information from the Fallout wiki:
It is possible for some settlers to be a Synth which may cause an attack on the settlement from The Institute.
As @DCShannon mentions in their comment, difficult is also likely a factor. A larger proportion of players seem to have settlements get attacked on survival mode, even if defense > food + water.
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How often do settlements get attacked?
The minimum chance for a settlement attack is 2% per day, on settlements that have at least 1 settler. I got a new twist for ya. A game or two ago I made Starlight Drive In my first settlement.How do Settlement attacks work?
Each unit of food and water production at the settlement increases the chance of attack by 0.1%. Each edible and/or drinkable item stored in a settlement's workbench increases the chance of attack by 0.1%. The minimum chance of an attack upon a settlement per day is 2%, regardless of defenses.How do you get raiders to attack your settlement?
If you have the wasteland workshop DLC, Build some Raider and Gunner Cages and power them up, when they get captured more attacks should happen. If you have the wasteland workshop DLC, Build some Raider and Gunner Cages and power them up, when they get captured more attacks should happen.Attack Frequency Solved - How to Reduce Settlement Attacks - Fallout 4
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