You can obtain this achievement by talking to the Item Scientist
at the Item Lab
in the Shopping Plaza
(see picture below) and enhance a weapon by sacrificing others until it's at +10.
What the description doesn't say, however, is that you can also enhance an armor piece to +10 and still get the achievement. I found it easier to enhance an armor piece than a weapon since you only need ten grinders
and some mesetas
instead of other weapons. By enhancing an armor piece, you also have the chance to obtain the following achievement by actually failing an enhancement :