In Avalon Code, you play as either Yumil and Tia, a young boy/girl duo born in a world that's on the verge of destruction. You've been having dreams about the world's end. One day, waking up from one of these dreams, you find a special book at your side. This book leads you on an adventure to explore the world, noting down all the elements that should be carried over when the world is reborn following its destruction, and rewriting all the elements that should be changed.
I thought this DS game was notable because it is the first 3-D RPG on the DS that I've seen to use actual un-deformed characters. It looks really good to boot. Probably one of the best-looking games on the DS to date.