Jason Rohrer’s Diamond Trust of London requires you to bribe opposing diamond agents, all while your opponent bribes yours. It feels like a German board game, but playing on the DS makes secret decisions possible. 

Gus Mastrapa at Paste magazine discusses the game’s possible commentary on business transactions:

Jason Rohrer’s previous games often had much to say about the way we live, die and all the stuff we do in between. It is tempting to search for some kind of commentary in this particular game’s theme. Diamond Trust of London offers no overt judgments around the business of the gem trade, but the rules of the game encourage the leveraging of your riches to stack the deck in your favor. Rather than attempt to create a narrative that paints the business as exploitative or dishonest, Roher uses the game’s underlying mechanics to paint the undertaking as one that encourages and maybe even requires misdeeds.