The Final Stand deathstreak is unlocked at lvl 39. Having the deathstreak on means that when you die 4 times in a row then on your next respawn when you are shot you may been knocked down to prone, you can crawl around and continue to use all of your different weapons. The deathstreak is similar to the perk Last Stand. The perk will continue to happen until you end your deathstreak. While in Final Stand, if you are not killed you are able to get back up.
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