Scent of the Past

This mission comes in two parts.

Part 1 involves selecting one of your six currently unlocked companions and doing a solo mission. Each choice has a different mission and set of rewards. Completing the case record to cover all options in part 1 rewards the 'Glimpse of the past' achievement.
 * Albus
 * Mission
 * Defeat Giselle
 * Rewards
 * A letter containing 300 training manuals
 * 'The student surpasses the teacher' achievement
 * Sion
 * Mission
 * Defeat Aizia and Garry
 * Rewards
 * Two letters containing their bounties, 1250 V each
 * The 'Hysteria' mastery
 * The 'A Strategic Retreat' mastery
 * Irene
 * Mission
 * Defeat Luna
 * Rewards
 * The 'A Hero Never Gives Up' mastery
 * The 'The Responsibility of a Hero' mastery
 * The 'Justice always wins' achievement
 * Heixing
 * Mission
 * Defeat two drones
 * Rewards
 * A letter containing 20 High-End Energy Extractors
 * Anne
 * Pre-mission choice
 * 'Drive away by force' the Dorori
 * Mission
 * Defeat the Dorori (you play as Anne)
 * Rewards
 * Defeating the Dorori can drop its masteries and troublemaker information
 * The cutscene for winning is the same as the cutscene for losing in the 'Ignore it' path
 * 'Ignore it' instead
 * A second set of options, which buff the Dorori according to the tooltips
 * Mission
 * Defeat Anne (you play as the Dorori)
 * Rewards
 * 'Waiting' mastery (rewarded on win or lose)
 * The cutscene changes depending on whether you win or lose
 * If you win,
 * If you lose,
 * Ray
 * Mission
 * Read through the dialogue
 * Rewards
 * 'A strict refusal' mastery

Part 2 sets your team to hunting monsters loose in the middle of the park. White Tiger gang members are on the other end of the park and also fight the monsters, and will engage you if you approach. Defeating the monsters will end the mission, even if gang members are still alive.