LUMINES REMASTERED

Just play CHALLENGE until the skins change. Achievement unlocked. FWIW, the hardest part of this game is figuring out what to do with the checkerboard blocks. You can find strategies online, but the tl;dr version is to arrange them in a 2x2 block in a corner. When the block is complete, the center will clear and you fill that with two more checkerboards, and so on. If you keep that corner your 'checkerboard corner' and never screw it up (keep a 1 block gap between it and the rest of your blocks), the game becomes a bit easier.