The Surge 2

The max level on your first playthrough for all gear and weapons will be X (Level 10). As you progress through the story, enemies will be higher and higher levels, allowing you to upgrade existing gear sets that you like to be in line with what you get from those enemies (the enemy's level corresponds to the component level they will drop). Just before the final boss, spend some time to upgrade a full gear set to maximum for this achievement (even if you don't plan to wear a full set together). In NG+ enemies will continue to level past X and you'll need to go through the process again up to XX if you miss this achievement on your first run.

To upgrade gear, you will need both scrap (aka money) as well as a certain number of parts cut from enemies. The first time you cut a piece off an enemy, you'll get the schematic for whatever gear they are wearing on the piece you cut off. You can find similar enemies or simply jump in a med bay to respawn the map and kill the same enemy for a new part (though bear in mind not every enemy will have a full set of armor on). Once you have cut the head, body, leg, and arm off an enemy to get a full set of schematics, continue to cut pieces off to get components and scrap for upgrading.

You can turn higher level components into lower level ones (gaining extra in the conversion) if needed, and each upgrade will cost more scrap. Once you have upgraded the head, body, two legs, and two arms from the same gear set, this achievement will unlock.