Complete the indicated task to unlock the corresponding character in Blackout mode.

Airborne: Reach Level 60 in Blackout mode.
Battle Hardened: Reach Level 80 Prestige in Blackout mode.
Frogman: Reach Level 40 in Blackout mode.
Mason: Unknown.
Mendez: Unknown.
Ranger: Reach Level 20 in Blackout mode.
Reznov: Unknown.
Seal: Reach Level 80 in Blackout mode.