How much would a tattoo cost if it said " the world you left behind" on my back?

it depends where you want it, how big you want it, the font type, how long it will take, do you want it colored in? just shaded? and the place you go to!

Call your local tattoo shop and ask. Every tattoo shop has different prices than other shops. Price also depends on a lot of different things. Size, location, color, detail etc. For example, one tattoo shop will charge you lets say $50. But the tattoo shop across the street charges you $80. Another example one place may charge you more if you get the tattoo on your arm rather than your thigh and another shop may charge the other way around. Give your local shop a call they'll be able to tell you exactly how much it'll be :]