Thanks! Actually, I'm planning to create different moving block (with color code) also move with different slower rate! For example the "player" slowdown by 0.5x, meanwhile the red block slowdown by 0.3x, green block 0.7x, etc.. So, it will add more challenge diversity.
I also want to experiment not only to make it slow, but in some point the "player" will move in reverse (I don't know will it still be fun or not though)