I pulled this from the GFQ board. I thought it was worthwhile. I think some of these will be hard to get.
Lightweight Challenges:
Escape death 5 times after being shot
Get 15 melee kills
Get 10 offense medals by killing ops near their objectives
Scavenger Challenges:
Get 2 kills without dying
Get 10 lethal grenade kills with resupplied grenades
Resupply 150 times with scavenger
Ghost Challenges:
Destroy 30 aircraft without killstreaks
Destroy 5 sentry guns
Kill 20 enemies while their spy plane or blackbird is up
Flak Jacket:
Plant/defuse 10 bombs in demolition
Survive 10 explosions
Throw back 5 enemy grenades
Hardline:
Earn and call in attack dogs
Get a 7 killstreak
Share 10 care packages with teammates
Hardened:
Get 30 kills through walls
Destroy 10 pieces of enemy equipment through walls
Shoot 200 bullets into enemy aircraft
Scout:
Get 30 headshots
Get 50 one shot one kills
Get 50 kills with secondary weapons
Steady Aim:
Get 150 hip-fire kills
Melee 2 enemies consecutively 3 times
Get 100 kills after sprinting
Sleight of Hand:
Get 150 kills while ADS
Reload and finish off the enemy you wounded 10 times (shoot, reload, kill X10)
Kill an enemy within 5 seconds of reloading 30 times
Warlord:
Get 25 frag or semtex kills
Get 5 multi-kills with grenades
Get 150 kills using guns with two attachments
Marathon:
Capture 15 flags
Get first blood 10 times
Run 26 miles using marathon
Ninja:
Get 15 backstabber medals
Plant the bomb in search and destroy 10 times
Get 150 kills using the suppressor attachment
Second Chance:
Get 3 headshot kills in second chance
Get 20 kills in second chance
In second chance, kill the guy who downed you 5 times
Hacker:
Destroy 25 equipment or explosives using hacker
Kill an enemy with claymores or c4 25 times
Kill 25 enemies within jammer or motion sensor radius
Tactical Mask:
Kill 20 enemies that are stunned by your concussion grenade
Kill 20 flashbanged enemies by your flashbang
Kill 20 enemies poisoned by your nova gas
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Lightweight Challenges:
Escape death 5 times after being shot
Get 15 melee kills
Get 10 offense medals by killing ops near their objectives
Scavenger Challenges:
Get 2 kills without dying
Get 10 lethal grenade kills with resupplied grenades
Resupply 150 times with scavenger
Ghost Challenges:
Destroy 30 aircraft without killstreaks
Destroy 5 sentry guns
Kill 20 enemies while their spy plane or blackbird is up
Flak Jacket:
Plant/defuse 10 bombs in demolition
Survive 10 explosions
Throw back 5 enemy grenades
Hardline:
Earn and call in attack dogs
Get a 7 killstreak
Share 10 care packages with teammates
Hardened:
Get 30 kills through walls
Destroy 10 pieces of enemy equipment through walls
Shoot 200 bullets into enemy aircraft
Scout:
Get 30 headshots
Get 50 one shot one kills
Get 50 kills with secondary weapons
Steady Aim:
Get 150 hip-fire kills
Melee 2 enemies consecutively 3 times
Get 100 kills after sprinting
Sleight of Hand:
Get 150 kills while ADS
Reload and finish off the enemy you wounded 10 times (shoot, reload, kill X10)
Kill an enemy within 5 seconds of reloading 30 times
Warlord:
Get 25 frag or semtex kills
Get 5 multi-kills with grenades
Get 150 kills using guns with two attachments
Marathon:
Capture 15 flags
Get first blood 10 times
Run 26 miles using marathon
Ninja:
Get 15 backstabber medals
Plant the bomb in search and destroy 10 times
Get 150 kills using the suppressor attachment
Second Chance:
Get 3 headshot kills in second chance
Get 20 kills in second chance
In second chance, kill the guy who downed you 5 times
Hacker:
Destroy 25 equipment or explosives using hacker
Kill an enemy with claymores or c4 25 times
Kill 25 enemies within jammer or motion sensor radius
Tactical Mask:
Kill 20 enemies that are stunned by your concussion grenade
Kill 20 flashbanged enemies by your flashbang
Kill 20 enemies poisoned by your nova gas
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