In short, to craft legendary Power Armor, you will need to get both legendary modules and cores. You can get legendary modules from the mole that resides over at the rusty pick, and you can earn cores through daily activities such as daily ops, quests, and events.
Once you have both, you can create Legendary Power Armor by going into your power armor crafting station and then switching to the modify section of the station. After this, click on any piece of armor and then hit legendary mods, and you should get a choice of creating the following legendary mods.
- Legendary mod one star - Requires one core and two modules
- Legendary mod two stars - Requires three cores and three modules
- Legendary mod three stars - Requires five cores and four modules.
Depending on how much of the materials you have, you should be able to create one of these legendary mods, and doing so will turn and create a legendary power armor piece for you. Doing this will also make that armor piece have a set of random effects depending on what mod is used to make the legendary power armor.
However, if you don't feel like using this method to get legendary power armor, you can always find it farming legendary enemies and even buy it from the mole merchant at the rusty pick for scrip.
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