Here is the full list of all 51 RedPixel achievements.
Complete level 1 in under 2.5 seconds
Complete level 2 in under 15 seconds
Complete level 3 in under 4.5 seconds
Complete level 4 in under 12 seconds
Complete level 5 in under 14 seconds
Complete level 6 in under 17 seconds
Complete level 7 in under 23 seconds
Complete level 8 in under 12 seconds
Complete level 9 in under 14 seconds
Complete level 10 in under 42 seconds
Complete level 11 in under 15 seconds
Complete level 12 in under 20 seconds
Complete level 13 in under 7 seconds
Complete level 14 in under 15 seconds
Complete level 15 in under 17 seconds
Complete level 16 in under 20 seconds
Complete level 17 in under 17 seconds
Complete level 18 in under 23 seconds
Complete level 19 in under 24 seconds
Complete level 20 in under 66 seconds
Complete level 21 in under 8 seconds
Complete level 22 in under 26 seconds
Complete level 23 in under 25 seconds
Complete level 24 in under 15 seconds
Complete level 25 in under 12 seconds
Complete level 26 in under 7 seconds
Complete level 27 in under 11 seconds
Complete level 28 in under 24 seconds
Complete level 29 in under 35 seconds
Complete level 30 in under 39 seconds
Complete level 31 in under 11 seconds
Complete level 32 in under 26 seconds
Complete level 33 in under 9 seconds
Complete level 34 in under 11 seconds
Complete level 35 in under 15 seconds
Complete level 36 in under 14 seconds
Complete level 37 in under 23 seconds
Complete level 38 in under 24 seconds
Complete level 39 in under 38 seconds
Complete level 40 in under 61 seconds
Complete level 41 in under 7 seconds
Complete level 42 in under 5 seconds
Complete level 43 in under 15 seconds
Complete level 44 in under 10 seconds
Complete level 45 in under 12 seconds
Complete level 46 in under 9 seconds
Complete level 47 in under 38 seconds
Complete level 48 in under 65 seconds
Complete level 49 in under 60 seconds
Complete level 50 in under 80 seconds
Complete the game!