Deathstreaks are Modern Warfare 2′s way of giving a helping hand to players that get killed a bunch of times in a row. They act the same as Killstreaks but in the opposite way, and work to prevent spawnkilling and allow players to get back on thier feet after playing poorly for a while.
DEATHSTREAKS:
3 Deaths – Painkiller: This Deathstreak reward allows you to take way more damage than usually possible for a short period of time after your spawn. Most players tend to use painkiller as the main deathstreak since it is the most generic and useful, and it also almost always lets you get at least one kill of your spawn. Painkiller is especially useful is enemies are in your base spawnkilling you and your team.
4 Deaths – Copycat: This Deathstreak allows you to steal the loadout of the enemy player who killed you. Probably the worst Deathstreak since most people have a loadout designed for themselves, and using another players can be hard to use at times. I would not recommend using this Deathstreak unless you just wanna mess around or get title rewards.
4 Deaths – Martyrdom: This Deathstreak makes you drop a grenade right after getting killed, which can often kill the person who killed you in close quarters. This is probably the deathstreak reward that is most used by people like tubers and hackers, since it only works to really annoy other players. Its pretty easy to dodge the grenade too, unless you are inside a building and cannot run away. I would definately use Painkiller over this as the main Deathstreak perk.
4 Deaths – Final Stand: Final Stand lets you potentially survive after getting killed by dropping down and bleeding for a short period of time before recovering. This works the same as the Last Stand perk, except you can use all your equipment and main weaponry, also, you get back up after a while on the ground. This is the second best deathstreak behind Painkiller, since it can be amazing if you were in the middle of a Killstreak and you have cheat death. It is also extremely annoying, since most players aim away once “killing” a player, making it easy for people with this to take you down.
SUMMARY:
Deathstreaks are not something you really want to worry about, cause if you get to use them lots… well, your sucking! Painkiller is the best bet, since it starts one death sooner and can be really helpful in almost any situation compared to the other Deathstreak “rewards”.

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