Here is the full list of all 40 METALLIC CHILD achievements.
Accomplish 100 triple kills.
Perform 200 Chain-skill attacks.
Collect all Fan-art.
Go on camera 20 times, for Miamo's live stream.
Help deliver Trevon's virus case 20 times.
Collect all Recor-Ds.
Open Daviny's box 20 times.
Change weapons 100 times during battle.
Be graded a D for battle 100 times.
Defeat 20 of Catherine's modified robots.
Equip a drone 100 times during battle.
Clear Terminal Creed.
Defeat all Metallic Childs.
Defeat the Metallic Child, Magna.
Defeat the Metallic Child, Lighton.
Deal 600 damage or more to an enemy in a single hit.
Defeat the Metallic Child, Spyden.
Defeat the Metallic Child, Flyer.
Defeat the Metallic Child, Shutty.
Perform 200 Take-downs.
Install 150 Super-cores.
Install 200 bugged and viral Cores.
Defeat the Metallic Child, Icela.
Defeat 3000 enemies.
Defeat the Metallic Child, Gigantic.
Defeat the Metallic Child, Controd.
Defeat the Metallic Child, Faceless.
Help retrieve Sly's weapons 20 times.
Rescue 20 survivors.
Accomplish 30 combos.
Be graded an S for battle 100 times.
Accomplish = double kills.
Install 150 Mini-cores.
Defeat the Metallic Child, Graver.
Experience a defeat in battle.
Defeat the Metallic Child, Fira.
Visit the various facilities of Life Stream.
Clear all Virtual Missions.
Accomplish 30 fantastic kills.
Repair Schrodinger 20 times.