Those who had played Halo 4's multiplayer before November 20 they can now have access to six new specialisations

The six class specializations - collectively known as Priority Alpha  were initially exclusive to Limited Edition copies of Halo 4. On the weekend, Xbox Live members who already have played Halo 4 multiplayer before November 20 will receive download codes providing access to the perks.

 from the six specializations, two are available to those who have played the game after November 20 in the form of Wetworks and Pionner but the player must have reach level 50 to unlock them.

Update: According to the official 343 Industries forum, Xbox Live users in Europe, the Middle East and Africa will not receive the offer as the offer was a pre-order initiative in those regions.

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