The combat of can be influenced by Legion Arms, special tools you can make and upgrade to give your character special abilities and techniques against the crazed puppets in Krat. There are many different types of Legion Arms you can find, with their own unique traits and modifications. A rare material must be collected in order to improve these powerful secondary weapons or craft entirely new ones.
Every Legion Arm has a limited number of uses tied to the Legion meter found in the lower left corner of the screen. Much like your other resources, you'll need to fast travel in back to a Stargazer and rest to replenish the Legion meter. As you unlock more Legion Arms in new areas later in the game, you are able to freely switch between Arms at any Stargazer or in the hub region of Hotel Krat.
You can increase the number of Legion Arm uses by investing Ergo into your Capacity and Advance stats when leveling up your character.
Although all the eight Legion Arms available in are given to you by talking to various NPCs you meet, you can make and upgrade these parts by collecting Legion Plugs. Many chests or defeated enemies could have Legion Plugs, making it a rare item to find as you go through the game. If you find a particular type of puppet that drops them more often, you may want to consider farming that foe for as many Legion Plugs as possible.
Once you have enough Legion Plugs, go to the Venigni Craft Machine to craft or improve your Legion Arms in whatever way you wish. More upgrades to the same Arm will inevitably cost more Legion Plugs than before, making it more and more difficult to raise that tool to its maximum potential. Thankfully, you can actually get the Legion Plugs you've spent back by resetting your Legion
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