The Crazy 8 works similar to the final season of Road Rules. Starting with 8 people, the 8 compete in a daily challenge, per usual challenge ways. 1 guy and 1 girl (or just 2 people if online) are deemed losers during said challenge, and are eligible for replacement.
The 2 losers must compete in an elimination task, which will determine if 0, 1 or 2 people leave. Anyone who leaves is replaced by a new competitor.
The cast cycles through 18 people total until the final Crazy 8 are determined. 2 more are eliminated, with the Final having 6 people, 3 of them becoming winners.