The First Descendant

This achievement has a pre-req of Mastery Rank 9, which unlocks this option from Silion at the far right side of Albion from the spawn point. You will need a minimum of 28 modules and 28,000 gold to do a total of seven combinations, as each one requires 4 modules and 4,000 gold. Talk to Silion when you're ready, then select a group of modules to combine and repeat six more times.
 

Note: As mentioned in the Road Map, many of the cumulative achievements in this game are finnicky, so I would suggest doing this all in succession, or at the very least in a single play session to ensure it unlocks properly. The tracking may reset if you log out of the game.