Getting to power level 130+ is relatively easy. The last 10-15 levels though can be a bit of a grind.
As you collect & equip higher power level gear, you will discover gear with higher base power levels (usually within a few levels of your current power level).
To reach level 150, you will need:
- All your equipped gear will need to be either Epic (purple), Legendary (Yellow), or Exotic (Orange).
- Each gear piece will need to have a BASE power level rating of 130. (a potential of 10 upgrades levels will make it 140)
- You need to equip & upgrade a major artifact to +10 (base of +1, boosted 9 times) as that will give you your final 10 levels between 140-150. (Major artifacts boost your overall power level rating +1 for each upgrade)
- You will need to upgrade each equipped piece of gear (including the two minor artifacts) to power level 140.
Upgrading your gear from 130 to 140 will take increasingly more resources, which is when the gear vendors & faction vendors will finally make themselves useful. Besides simply collecting resources from strongboxes, enemies, & mission rewards, you will be able to use fragments to purchase resources that you need to upgrade when you need "just a little more" to be able to upgrade gear to the next power level.
Overall, it can be a little bit of a grind on these last 10-20 power levels, but if you pick one main character to use for the main mission chains, you should be able to easily get this achievement in the process of completing the other achievements.