| 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.
Since this achievement is earned when you beat Level T-7, there is no preferred character for this achievement.
Similar to Boldly Gone, this achievement is not incredibly hard. It is just quite time-consuming. In fact you will have to beat a minimum of 64 levels in order to get this achievement (55 for the Main Tunnel, 2 for the L-Tunnel, and 7 from the T-Tunnel).
Beating Level T-7 is the only way to earn this achievement, and to reach this level, you will have to beat the T-Tunnel, which its location is about the tip of the Main Tunnel. For more details about Level T-7, click here.
The instructions used to be "locate the first wormhole," with a lowercase W, implying that Player 03 may have originally planned to feature more than one wormhole in the game and/or plot. But the game developer implied that he forgot why he changed the instructions, so we no longer know the original plot.