Below is a walkthrough for the Testaments Training support request in The Legend of Heroes: Trails from Zero. You can pick up this request from the terminal in Chapter 2.
Client: Abbas
Salary: 2000 mira
Head on over to the Downtown District then make your way to Trinity. Speak with Abbas who is behind the counter to accept his request. A fight will then trigger against 4 Testaments (make sure to scan each one!). After you defeat them, you’ll then take on 4 members of the Saber Vipers (make sure to scan each one!). Once you defeat this lot, you’ll then have to defeat all 8 of the bickering clans! Defeat them all to complete the request!