Ever run into that problem where a nice, shiny, powerful character decides to join your party and compels you to throw your finest quartz and equipment on them, only to have them disappear just moments later taking all your valuable equipment with them? Well, this guide is meant to address specifically that problem. I will try to keep this as spoiler-free as possible, tagging all join/leave points that mention events with spoilers. I will also be omitting most short story sections where characters may leave you but you cannot encounter any enemies.

• Start with Estelle
  
• Anelace joins (Upon reaching Le Locle)

• Anelace leaves, returning items (Start of chapter)
  
• Scherazard OR Agate joins and is locked in (Start of chapter)
  
• Kevin joins (After talking to the orphanage witness)
  
• Kevin leaves, returning items (The moment you enter Ruan with him. You should save your monster extermination quests for when he is in your party)
  
• Olivier and Dorothy join, the latter as an escortee (After talking to all three witnesses and returning to Ruan. You should save the Sapphirl Tower photo quest for when you have Dorothy, though it may be better to clear the chests another time)
  
• Kloe joins (Upon going to the Jenis Royal Academy to investigate. You will be left alone with Kloe for some time but there are no monsters until your party rejoins)
  
• Dorothy leaves (After the first monster in the Jenis Royal Academy dungeon)

• Tita joins. Tita locked in with Scherazard/Agate for the rest of the chapter (After returning from the earthquake at Sanktheim Gate. You may now choose party members)
  
• Zin joins and Tita free to use (After defeating the end chapter boss)

• Renne joins as an escortee (After finding Renne)
  
• Scherazard/Agate, Tita, and Renne leave, taking items. Party locked as Estelle, Zin, Olivier, and Kloe (After returning to the guild with Renne)
  
• Party restored without Olivier. Scherazard/Agate and Tita locked in. Olivier takes items with him as he leaves. There is a brief section where you only have Scherazard/Agate, Tita, and Renne, but there are no enemies. (After returning to the guild from investigating the threat letters)
  
• All members leave party, taking items (After finding Renne for the second time)
  
• Kevin joins (Upon reaching the Gurune Gate wall. Immediate battle)
  
• Agate/Scherazard, the one you didn’t pick in Chapter 1, joins (Upon returning to the guild)
  
• Julia joins temporarily and then leaves (Septium tank and Captain Amalthea battles only. Note: Julia isn’t a proper character for these two battles. You can control her but her quartz is a small selection of high level spells without their lower level equivalents. You also can’t access her quartz/equipment and so can’t steal any items)
  
• Party restored. Agate/Scherazard, the one you didn’t pick, joins permanently. Your original partner is still locked while in Grancel (After the end chapter battle)

• Perspective switch to Joshua after boarding the airliner before the main Chapter 4 starts. Josette, Kyle, and Don join as attacking escortees. Kyle and Don leave for the boss fight, while Josette fights but will die easily (with no penalty to you).
  
• Scherazard locked into party for your entire time in Rolent regardless of who you picked. Agate will be free to use.
  
• Party locked in as Estelle, Schera, Kloe, and Tita. Male characters do not return items, but it's a short segment with only one forced battle. (After the night patrol)
  
• Party restored with Scherazard locked in (After returning to the guild from the Perzel farm)

• Agate locked into party (Beginning of chapter)
  
• Agate leaves, taking items. Tita locked in (After reporting in from exterminating the monsters)
  
• Tita leaves, taking items. No battles for this section (After returning to Ravennue from the Abandoned Mine)
  
• Agate and Tita join and are locked in for the rest of the chapter (After the scenes at the Arseille)

• Estelle forms a party with any 3 characters at the start of the chapter (You can remove items manually from other characters). All other characters leave for Valleria Lakeshore.
  
• Kevin joins at Valleria Lakeshore. You may swap party members freely there, and this does not expire existing sidequests or progress NPC dialogue.
  
• Kevin is locked in once you choose to progress the main story. The party you form cannot be changed for the next dungeon.
  
• Estelle separated from party (After reaching the end of the facility. There is a short segment where you have control over the rest of your party, but you cannot access the equipment, orbment, and item menus during this time.
  
• Joshua joins Estelle (After the battle with Gilbert)

• Party restored except for Olivier, who will be gone for the next two chapters, returning items. Joshua is locked in from here onwards (Beginning of chapter)
  
• First Tower – Free to choose
  
• Second Tower – Zin locked in
  
• Third Tower – Scherazard locked in
  
• Fourth Tower – Free to choose

• Kevin and Kloe leave, returning items. (Beginning of chapter)
  
• Anelace and Kurt join temporarily (Jenis Royal Academy sidequest. You get a screen where you can transfer items. There is a short section with only Joshua before this but there are no battles)
  
• Current party locked in (Upon entering Grancel after delivering the ZFGs)

• All characters restored. Kloe is auto-equipped with upgraded equipment but Olivier and Kevin remain the same. (Beginning of chapter)
  
• Josette joins (Second map area of Cradle)
  
• Josette required for progress (Entire sequence in the Glorious)
  
• Julia and Mueller join (Return to the Arseille after reaching the Axis Pillar entrance)
  
• Current party locked in (Loewe fight onwards. Note: You do not get to change Joshua's equipment at anytime from the Loewe fight to the final boss.)
  
• Joshua leaves (After the Loewe fight)
  
• Joshua joins (Start of the Weissmann fight)