Cartographer Unlock A Map

It is basically a bug or an unfinished piece of code. From this thread you can see that many other people have it and one of the opinions is:

This is a bug, an error, in the game. A "miser run" is one in which you avoid collecting coins, but in this case no goal number has been set. "Desc" is short for for description. The programer placed this temporary text to remind himself (or someone else) to place description text for the miser run. In the original Temple Run game a Miser Run was running 500 meters without collecting any coins, so either this was simply a repeat performance it it was actually code that was copied over from the former game, but not completed. If you look in the main current objectives list you'll see that it does not show up. I was able to make this objective disappear by starting a run and simply running off the first ledge without jumping.

So don't worry about it, it's just there to take some free space. It might be updated in the future with new objectives(I hope)

I collected all 10 artifacts & after that nothing happens. The objective to collect them all is done and there's no other objectives & still at level 9. So disappointing. Just letting you know. Here's a list of all 10 ring artifacts: Infinite Loop, Angel Wings, Twisted Root, Floating Island, Sky Clasp, Demon Claw, Ruby Shard, Caves Maw, Mystic Rocks & Idol's Curse.

In addition, here is a list of the Christmas-themed artifacts added in the December 2013 update: a candy cane, present, wreath, stocking, and a piece of holly. Once you collect all of Christmas artifacts, your character gets to wear a Christmas hat, and you can play as Santa for 60 gems.

Further addition: there are 5 Valentine's day related artifacts available in chests in a recent update as well.