Question: how to watch old episodes of the challenge?
Answer: If you have cable, MTV.com has some Challenge seasons. ... 
If you're looking to watch The Challenge and you're main go is just The Challenge, I recommend Philo. ... 
Sling TV is another option, though more expensive. ... 
In July, 2020 CBS All Access added The Challenge seasons 11-13; 15-31 on their service.