This is level 54 of the Main Tunnel.
In this level, I recommend using the Runner since you have better controls over her. If you use the Skater or the Lizard, you may easily crash onto the crumbling tiles, and since they are a big threat in this level (Like Level 10 and Level 39), this may become deadly.
If you want to pass this level, try to avoid the crumbling tiles as much as possible. By all means except from dying, keep away from them. This is a major strategy of the level. If you can do this, your chances of beating this level will surely increase.