Intrinsic Games' debut title is mind-bending and awesome, but very short.
Divergent Shift is a puzzle platformer with an interesting gameplay mechanic that has each DS screen functioning as a reflection of the other. The difference is that both screens offer different environments that you have to lead two characters through. This makes for some very challenging puzzles that require you to comprehend two playfields at once in order to succeed.
The game features simple controls that are laid out for you in a few single-screen introductory levels. All your heroine can do is jump, slide, and push boxes. After a story-related mishap, you're launched into the first mirror-like gameplay mechanic. You have to lead two versions of the main character through tricky environments, with the caveat being that both characters are safe as long as one or the other is safe.
At various intervals you must control the main character's shadow as well. In these cases, both characters have to be on safe ground to be okay, and while every move you make is reflected on both screens, they can move differently (e.g. if one is hanging on a platform, the other can move from left to right without the other one budging).
Both mechanics lead to really interesting puzzles that are fun, challenging, and rewarding. The final levels belong in the top tier of 2D platforming levels. Unfortunately, you'll reach them within two hours, as the game consists of about 25 short levels in total. There's a good deal of challenge, and a mildly appealing time trial section that leads to the unlocking of a few more levels. There are also journal entries you can find that unlock more levels and give the light story a little more context.
Still, there isn't much to come back to after you beat it, even though the short ride through the game is totally worth it. If you're satisfied with a short and sweet puzzle platformer for under $10, then Divergent Shift is right in your wheelhouse.