Bless Unleashed

In order to get this achievement you need to expand your bag by 20 slots. This can be done in a few ways. As you level up you'll get some expansion tickets here and there, and you can also buy tickets for it in the lumena shop (waste though). The quickest way is to keep an eye on the minimap for treasure chest icons. These are personal chests that give you a bag piece, with 4 you can head to a bag merchant (you can find them in many towns) and they will trade you 1 bag space for the 4 pieces. I got this in the 3rd big region, so there are way more than enough chests to get this. I've read you can get 100 spaces from the personal chests, which means 400 of them, though I'm not sure if that's true. As far as I know there is no map out there for the game yet, but there are more than enough that you shouldn't have problems getting this.