The Ghoulie Mastery camouflage will carry over to MW3.

The free Mastery Ghoulie camo, which features a vibrant design that combines shades of green, blue, and purple, reminiscent of the color palette associated with the eerie aura that players can obtain by beating the game.

You can get the “Ghouls” camouflage in MW2 by playing in the “Ghosts” event. The Ghoul camouflage will be available on October 24th. Any weapons or camos you unlock during The Haunting event will also carry over to Modern Warfare 3 when it launches on November 10th. So if you manage to unlock the Ghoulie Camouflage in MW2 and Warzone, you will be able to use it in MW2 or MW3. While not all content will carry over, exclusive items such as the Ghoul camo will be available.

To unlock the Ghoul camo in MW2 and Warzone, you need to collect 1000 souls in the Soul Capture event during The Haunting. This will permanently unlock the Mastery camo on your account, and you won’t have to spend souls to get other rewards first.