Promo originally available through Santa's Renegades.
There are two sides: Dangerous Pit and The Narrows.
Dangerous Pit: Pick up your speed before the chasm! If you are going less than speed 5 when you cross the line, you will take damage! If you are going to slow, take dent cards equal to 5 minus your speed. If you end your movement in the abyss, take any necessary dents and then don't refill your hand. (Exact same track was previously available for older version of the game - The Leap of Death)
The Narrows: Follow normal rules, but be careful! This side will require some careful maneuvering!
For more information, visit the BGG listing.