The echochrome game adds a unique collection and gameplay compared to your original PSP Best Hits.

User Rating: 8.5 | echochrome PSP
echochrome, a white and black art style game, gives the game unique style and gameplay. The main features are:
-Play levels in the atelier and create your own in the portfolio.
-Includes 56 levels (+40 levels if you get the expansion pack)
-Play freeform just for fun.
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In the echochrome game, you control a stick like character, which walks around to collect shadows, or "echoes". You must move the camera and change the angle to make the character reach the echoes.
The game hardens and the puzzles become more harder to complete. In order to complete them, you must apply five rules of perspective (you don't have to use them all; you can use them more than once). Without them, you cannot collect the echoes and beat the level.
I bought the add-on game, which includes the whole game, plus 40 levels.
This game deserves a 8.7 because of the difficulty. You will realize that the levels become so hard, its hard to beat them and you finally figure it out after 30 minutes or so. But it could be different for everyone. I took away the 1.3 for the difficulty and levels.
So if you are interested in this fun game, download the demo first from the PStore, and you may just be in the craving for echochrome yourself!