Anyone who played multiplayer in Halo 4 before November 20 is now getting access to six class-based specialisations previously available only to those who purchased the game's Limited Edition. Emails with download codes went out Friday evening, according to tipsters.
"Specialisation Priority Alpha," is the codename for the DLC package unlocking the modes. You earned it if you played Halo 4 multiplayer sometime before November 20. Specialisations offer additional armours and abilities and another 10 ranks. They become available once you reach level 50 in multiplayer.
If you missed the November 20 window, the "wetworks" and "pioneer" specialisations are still unlockable after level 50, but not the rest. For now.