The two teams have merged.
The challenge is going to be an editing contest. Everyone has until 6:00 PM EST on day eighteen to make as many mainspace edits as possible. The person who makes the most mainspace edits will win immunity. In the event of a tie, the two people with the most edits will win immunity. In the event of a three way-tie, nobody will win immunity. After the challenge, one person will be chosen to receive an e-mail about the hidden immunity idol.
Here are the starting edit counts:
To check edit count, use this.