Hey, I was just wondering that in order to achieve the mostly flesh and steel achievement, can you still purchase equipment upgrades such as the mask optics or something like the combat sleep darts? The achievement definition states "Finish the game without purchasing any supernatural powers or enhancements, besides Blink". It is the enhancements part of the definition that is making me unsure, thanks for any help.

Enhancements are the passive bonuses you can unlock with runes.

So I would be okay to purchase equipment upgrades?

Yes

Thanks for the help.