Here is the full list of all 21 Ballrun 3D Marble Maze Speedrun achievements.
Navigate the maze without touching the walls
Reached the halfway checkpoint
Completed all checkpoints
Completed the maze without falling 50 times or more
Completed the maze without falling 10 times or more
Completed the maze without falling once
Completed the maze in under 30 minutes
Completed the maze in under 20 minutes
Completed the maze in under 10 minutes
Reached the reverse halfway checkpoint
Completed all reverse checkpoints
Completed the reverse maze without falling 50 times or more
Completed the reverse maze without falling 10 times or more
Completed the reverse maze without falling once
Completed the reverse maze in under 30 minutes
Completed the reverse maze in under 20 minutes
Completed the reverse maze in under 10 minutes
Completed the maze without falling 25 times or more
Completed the reverse maze without falling 25 times or more