How do you unlock each party member?

There are a lot of characters to unlock. What are the pre-requisites and what do you have to do to get them?

Solution 1:

A handful of characters are obtained via story, namely these:

• Elma (you start the game with her)
• Lin (you get her during chapter 1)
• Doug (you unlock him after chapter 3)
• Gwin (you unlock him after chapter 3)
• Irina (you unlock her after chapter 3)
• Lao (you unlock him during chapter 4)
• L (you unlock him after chapter 4)

This gets you a pretty good sized party, but there are plenty more characters to unlock. Almost all of them require you do affinity missions (plus, there are some other pre-requisites like level and story chapter). They are:

• H.B.: You have to be level 12, have beaten chapter 3, and complete the affinity mission "A New Rival" (this is in the administrative district)
• Yelv: You have to be level 15, have beaten chapter 3, and complete the affinity mission "Meeting Yelv" (this is in the commercial district)
• Alexa: You have to have beaten chapter 4, have taken the basic mission "Guinea Pig Wanted" (you do not have to complete it), and then take the affinity mission "Weaponised" (this is in the test hangar in the industrial district)
• Phog: You have to be level 14, have beaten chapter 4, have taken the basic mission "Backup Request" (does not have to be completed), and then you take the affinity mission "Froggy Dilemma" (this is right below the administrative district, in the residential district)
• Boz: You have to be level 20 and have started the basic mission "Backup Request" (does not have to be completed), then you have to take the affinity mission "The Mad Monk" (this is in the commercial district I believe)
• Frye: You have to be level 20, have beaten chapter 4, and start the affinity mission "Bottoms Up" at night (this is in the industrial district)
• Hope: You have to be at least level 21, have beaten chapter 4, and taken the basic mission "Marry Me" (does not have to be completed). After this, you have to take the "Hope Springs Eternal" affinity mission (this is in the residential district)
• Murderess: You have to be at least level 23 and have beaten chapter 4, then take the "My Dream" affinity mission (this is in the administrative district)
• Nagi: You have to have beaten chapter 8, then take the affinity mission "Nagi Time" (this is available in the BLADE barracks)
• Celica: You have to have beaten chapter 9, and finished the "Manhunt" affinity mission. After this, you can take the "New in New LA" affinity mission (this is available in the industrial district and requires level 44)

And the main reason I wrote this guide was to clear up confusion surrounding the final unlockable character, Mia. There's a long chain of quests to unlock her, and not a lot of information on how the quests work. You have to:

• Complete the "Mamma Mia" mission after chapter 3 (this is available in the administrative district by talking to her)
• Complete the "Adventure" mission in Noctilum after chapter 5 - she is in the Skybound Coil Tree
• Complete the "Mighty Mia" mission after chapter 6 - she is on the leaning ring in Oblivia
• Complete "A Girls Wings" (this is available after chapter 9 in the test hangar)
• Complete Mia's normal mission in Sylvalum, available after Chapter 10.
• Complete the Definian event chain (starts in chapter 11): Attack on Biahno Hills, Water Woes, The Miracle Maker, Rites of Ruin, Good Fortun, Definian Downfall
• Complete the Alex chain: Alien Nation, Shotgun Diplomacy, The Line of Fire, Alex's Last Stand
• Complete the Professor B chain: Mystery Man, Professor B's Return
• Survey 65% of Cauldros (not 80%, as most places will say)
• Head to the Ganglion Antropolis and look for a surveyable item that you cannot reach - Mia is being kept in a trailer-like structure near the back of the facility - this will start the "Mia is Missing" mission.