| It's just so frustrating that I have to start over every time I fall.
This achievement is rather difficult and is considered quite hard. Due to its hard difficulty, the power cell reward for this achievement is higher than most achievements. Infinite Mode level achievements are usually not affected by this and they still keep their 25-75 power cell rewards if not affected.
Note: Since you can only get this achievement with the Ice Skater, he will be the only recommended character.
This is one of the hardest explore mode achievements, and this is why it has a reward of 500 power cells. You will need skill and luck.
Jump to the right at the beginning, so you float up and can re-enter the tunnel. To perform this correctly, wait for an instant after respawing, then hold right and do a high jump late, and then hold left once you leave the tunnel. Fall on the next patch of ice tiles, then continue. When the platform ends, jump to the patch on the left. Continue again, and this time when the patch ends, exit the tunnel to the left or right and re-enter to finish the level. Be careful not to change gravity at this stage, as that makes exiting the tunnel very hard. The right side needs a harder timing to pull off, but the left side has tiles at the very end that can prevent you from reentering the tunnel. Choose based on personal preference.
If you are struggling to get the achievement, you can simply practice the first and third jumps. They are the hardest, as exiting and re-entering the tunnel is not easy in levels with 6 sides. Use repetition to master landing the first jump and the transition to the second. For the third jump, you will need to find a way to reach the correct platform, then use that route to get there and repeatedly practice the third jump. After you are satisfied with both of those, combine the two to get the achievement.