You need to beat all the storylines of all 20 base-game characters in Soul Chronicle mode.
Each have a different number of fight and events, describe in the following list.

You can play anyone in any order but some are not available from scratch:

• Grøh's storyline unlocks Azwel's.
  
• Ivy's unlocks Cervantes'.
  
• Nightmare's unlocks Siegfried's.

Final event for Raphael and Zasalamel can be unlocked in Libra of Soul (side quests) but aren’t needed for the trophy.

DLC Storylines are not needed for the achievement.

• Mitsurugi: 5 fights / 6 events
  
• Taki: 6 fights / 6 events
  
• Kilik: 3 fights / 5 events
  
• Maxi: 6 fights / 6 events
  
• Xianghua: 5 fights / 7 events
  
• Grøh: 8 fights / 9 events
  
• Azwel: 4 fights / 6 events*
  
• Ivy: 4 fights / 7 events
  
• Cervantes: 5 fights / 8 events*
  
• Seong Mi-na: 6 fights / 7 events
  
• Astaroth: 5 fights / 6 events
  
• Nightmare: 5 fights / 5 events
  
• Siegfried: 4 fights / 7 events*
  
• Sophitia: 4 fights / 7 events
  
• Voldo: 5 fights / 7 events
  
• Yoshimitsu: 6 fights / 7 events
  
• Raphael: 6 fights / 7 events**
  
• Talim: 4 fights / 6 events
  
• Zasalamel: no fight / 8 events**
  
• Geralt! 6 fights/ 6 events

* Grøh's storyline unlocks Azwel's, Ivy's unlocks Cervantes' and Nightmare's unlocks Siegfried's.

** Final event for Raphael and Zasalamel can be unlocked in Libra of Soul (side quests) but aren’t needed for the trophy.