Some of these imitate Perk-a-Colas, while others imitate Power-Ups. They can also easily be lost, usually if the player does not make use of the upgrade. The player can have multiple upgrades at once (although some may cancel/interfere with others), and they carry over to different game sessions and maps.
These upgrades only take effect and can be acquired on the maps Green Run, Great Leap Forward, and Resolution 1295 (only present on the major modes TranZit, Die Rise, and Buried and not present in any Survival, Grief, and Turned modes). Persistent Upgrades, commonly referred as ' Perma-Perks', are unlockable upgrades that the player can gain through unique methods in Call of Duty: Black Ops II.
