List of Halo 4 commendations/Player

Dawn
Complete the campaign mission Dawn on Legendary difficulty

Requiem
Complete the campaign mission Requiem on Legendary difficulty

Forerunner
Complete the campaign mission Forerunner on Legendary difficulty

Infinity
Complete the campaign mission Infinity on Legendary difficulty

Reclaimer
Complete the campaign mission Reclaimer on Legendary difficulty

Shutdown
Complete the campaign mission Shutdown on Legendary difficulty

Composer
Complete the campaign mission Composer on Legendary difficulty

Midnight
Complete the campaign mission Midnight on Legendary difficulty

Legend
Complete all of the following commendations: Dawn, Requiem, Forerunner, Infinity, Reclaimer, Shutdown, Composer, Midnight

Spartan Slayer
Take out enemy Spartans

Bullet in the Brain
Take out enemy Spartans with headshots

First Strike
Get the first kill in a match

Multikill
Earn any of these 8 medals: Double Kill, Triple Kill, Overkill, Killtacular, Killtrocity, Killamanjaro, Killtastrophe, Killpocalypse

Assassin
Assassinate enemy Spartans.

Spartan Spree
Earn any of these 7 medals: Killing Spree, Killing Frenzy, Running Riot, Rampage, Untouchable, Invincible, Inconceivable

Assistant
Earn any of these 4 medals: Assist, Vehicle Destroy Assist, Distraction, EMP Assist

Protector
Earn any of these 3 medals: Protector, Guardian Angel, Savior

Close Quarters
Earn any of these 3 medals: Melee, Beat Down, Bulltrue

Combat Opportunity
Earn any of these 5 medals: Killjoy, Headcase, From the Grave, Reload This, Showstopper

Payback
Kill the enemy Spartan that just killed you

Avenger
Kill an enemy Spartan that just killed a teammate

From the Brink
Kill an enemy Spartan while close to death

Hail of Death
Call in personal ordnance.

Perfection
Complete a match without dying and get at least 15 kills

Exterminator
Killed every enemy Spartan that finished the match