Zombie Repeller

On a Mythic map, killed 2 Zombies during a ranked or social match.

Defend This

On a Legendary map, got a flag melee kill during a ranked or social match.

Campaign Complete: Legendary

Completed the Campaign on Legendary difficulty.

Campaign Complete: Heroic

Completed the Campaign on Heroic difficulty.

Alas, Poor Yorick

On a Legendary map, got 3 Oddball melee kills during a ranked or social match.

Too Close to the Sun

Destroyed a banshee with the spartan laser or missile pod in a ranked playlist or in campaign.

Vidmaster Challenge: Lightswitch

Got the rank of Lieutenant in any playlist in the new EXP progression system.

Spartan Officer

True veteran of many battles, you are a Spartan Officer.

Came… From… Behind

On a Legendary map, got 3 assassinations during a ranked or social match.

Double Double

On a Legendary map, got two Double Kills during a ranked or social match.

Road Rage

On a Legendary map, got 5 Warthog chaingun kills during a ranked or social match.

Delicious Brains

On a Mythic map, infected 2 humans during a ranked or social match.

Vidmaster Challenge: Brainpan

Found all the hidden skulls on the Mythic maps.

Heretic Skull

On Heretic, found the hidden skull.

Citadel Skull

On Citadel, found the hidden skull.

Longshore Skull

On Longshore, found the hidden skull.

Used Car Salesman

Destroyed a vehicle that has three enemies in it in a ranked playlist or in campaign.

Have Fun Respawning

On a Mythic map, got an Extermination during a ranked or social match.

Tank Dropper

On a Mythic map, got a kill on another player while in monitor mode.

Up Close and Personal

Killed 5 enemies by melee or assassination in a ranked free for all playlist.

Iron

Claimed Iron skull.

Orbital Skull

On Orbital, found the hidden skull.

UNSC Spartan

Promoted to Sergeant. Proven in combat, you are a Spartan.

Awww, Too Bad

On a Mythic map, got a Killjoy medal during a ranked or social match.

Assembly Skull

On Assembly, found the hidden skull.

Sandbox Skull

On Sandbox, found the hidden skull.

… Get the Horns

On a Mythic map, got a Bulltrue medal during a ranked or social match.

Mongoose Mowdown

Splattered an enemy with the mongoose in a ranked free for all playlist.

Graduate

Graduated from basic training. Stick with it to earn your Spartan Insignia.

Campaign Complete: Normal

Completed the Campaign on Normal difficulty.

Cleansing

Completed the fifth mission of the Campaign.

Fog

Claimed Fog skull.

The Road

Completed the third mission of the Campaign.

Maybe Next Time Buddy

Boarded the same vehicle within 10 seconds after being boarded in any free for all playlist.

Holdout

Completed the second mission of the Campaign.

Landfall

Completed the first mission of the Campaign.

MVP

Earned the MVP in a ranked playlist.

Return

Completed the final mission of the Campaign.

Mythic

Claimed Mythic skull.

The Key

Completed the eighth mission of the Campaign.

Tilt

Claimed Tilt skull.

Last Stand

Completed the seventh mission of the Campaign.

Thunderstorm

Claimed Thunderstorm skull.

Refuge

Completed the sixth mission of the Campaign.

Famine

Claimed Famine skull.

Fear the Pink Mist

Killed 5 enemies with the needler in a ranked free for all playlist or in campaign.

Assault

Completed the fourth mission of the Campaign.

Catch

Claimed Catch skull.

Tough Luck

Claimed Tough Luck skull.

Black Eye

Claimed Black Eye skull.