"Crowd Control" - Use one grenade to kill 5 enemies.
"Cap One" - Get 500 headshots in campaign.
"Stick It To 'Em" - Stick 50 Enemies in campaign.
"When In Doubt, Run" - Finish a mission on Legendary without using any grenades/health packs.
"Finish Him" - Assassinate 50 enemies in Campaign.
"Why Me?" - Complete All Missions within 25 minutes. (Normal, Heroic, Legendary)
"Blame Stosh" - Get an Assassination on a Cheiftan.
"Bird's Eye View" - Destroy 25 Enemy Banshees in Campaign (Normal, Heroic, Legendary)
"Ascending Into Hell" - Finish the First Mission. (Normal, Heroic, Legendary)
"Fight To The Finish" - Finish round 50 in FireFight