Orcs & Elves. Supposedly, this is to commemorate the release of its sequel, Orcs & Elves II, on mobile phones (you can read id's press release here regarding that). We could care less about what it's commemorating, to be honest. We just like cheap games!
If you were on the fence regarding the game, maybe this new price of $19.99 will bring you down? Or, did you just not care for the title, regardless of price?
[Via DS Village]