This is the sixth and next to last level of the T-Tunnel.
This level is mostly filled with crumbling tiles that will most likely give you little ground to land on. Almost every character can complete this, but characters with high speed (i.e. Skater, Bunny, and sometimes the Angel) have the most trouble with it and require some skills and reflexes.
Throughout the tunnel, you can focus on going either left or right, each character's performance varies on which direction you choose. The left side of the tunnel is better suited for high jumping characters (i.e. Lizard and Jack-o-Lantern) or those with an ability to stay in the tunnel (i.e. Duplicator, Child, Student, and Pastafarian), the right side is the easiest and is most suited for average to low jumping characters (i.e. Runner and Gentleman).
No matter which direction you choose, most characters will do great on either side. You can even mix them up a bit. Take giant leaps to get pass most of the level when using the Lizard or the Jack-o-Lantern. For the Gentleman, the power cells in the level may affect your gameplay when playing as the Gentleman. Be aware that the Duplicator's duplicates can walk over crumbling tiles and dislodge them, causing trouble in the level, so keep an eye on this.