The return of Rebirth Island in season three of Call of Duty: Modern Warfare 3 comes with a bunch of new and exciting rewards for players to collect. One of them is the Welcome to the Mainframe camo.

Call of Duty often requires players to complete a series of challenges in order to access certain rewards, and this camo is no different. It may be considered the longest camo challenge in CoD history. Here's what you need to know about how to get the Welcome to Mainframe camo in MW3.

To obtain the Welcome to the Mainframe camo, players will need to regularly interact with the biometric scanners scattered throughout Rebirth Island. Specifically, you will need to do this a total of 27 times on unique days to obtain the camo. These scanners offer multiple levels of key cards as rewards, which can be traded in for valuable loot at Buy Stations.

There are a total of nine biometric scanners scattered across the map of Rebirth Island. The locations for the scanners are permanent, but not visible on the map.