See Challenge # 112. This is a roamer who searches what was left of lakes and ponds in the Waste and trades those goods when the Roamer's Meet comes. I originally wanted this to be red.

Interesting. I can't say I expected to see a Surrakar among the Roamers!
When compared to Master Thief, I think this can have a much lower cost. You're giving your opponent an unblockable 3/3 in exchange for whatever artifact you've taken, which is pretty good.

I reduced the cost and made the exchange optional. I picked Surrakar because there's not a whole lot in the way of blue races. Faerie and merfolk seemed out of place (I'm not a fan of merfolk on land). Vedalken seem like they should be in Rohn or Teruga, and while I imagine there are human Roamers I just find human boring as the "go-to" race for things. That left Surrakar and Bird in my head as the creature options for something intelligent enough to have a class as part of its creature type as amphibian is so rarely used I totally forgot about it (though you could argue Surrakar is hardly used not existing outside of Zendikar). I didn't see the creature as having flying, so I didn't think it should be an aven, so I ended up at Surrakar.

On Merfolk on land: There are waterways and large bodies of water on Danahar. I didn't mention them so as not to skew thoughts of civilizations toward blue.