Assault on the Control Room

Halo CE: Complete Assault on the Control Room.

Spoilsport

Kill 100 Jackals.

The Silent Cartographer

Halo CE: Complete The Silent Cartographer.

Where Am I?

Complete 10 missions or multiplayer games.

Truth and Reconciliation

Halo CE: Complete The Truth and Reconciliation.

Close Quarters Combat

Halo CE: Complete The Truth and Reconciliation with at least four rounds left in your Sniper Rifle.

My Buddy Chips

Halo CE: Fight alongside Chips Dubbo and listen to his words of wisdom.

Halo

Halo CE: Complete Halo.

Pillar of Autumn

Halo CE: Complete The Pillar of Autumn.

Didn't Like This Ship Anyways

Halo CE: Beat the par time on The Pillar of Autumn.

Balaho's Most Wanted

Kill 100 Grunts.

Confused Callouts

Halo: Reach: Trigger a humorous callout on your HUD's position indicator.

Easy to Overlook

Halo: Reach: Access hidden UNSC radio chatter.

The One Percent

Kill 100 Elites.

New Ways to Save a Buck

Halo: Reach: Hear a familiar voice on New Alexandria.

Parting the Sea

Halo: Reach: Beat the par score on Exodus.

Into The Howling Dark

Halo: Reach: Complete Exodus.

The Humble Beginnings of Wiljax Brantley

Halo: Reach: Now that's a value meal.

No Picnic

Halo: Reach: Observe a grizzly scene on New Alexandria.

Insomnia

Halo: Reach: Beat the par score on Long Night of Solace.

Sabre Metrics

Halo: Reach: Beat the par time on Long Night of Solace.

You Flew Pretty Good

Halo: Reach: Complete Long Night of Solace.

Wake Up Buttercup

Halo: Reach: Destroy the Corvette's engines & escort in under 3 minutes during Long Night of Solace

Bite The Hand

Kill a 343 developer in matchmaking or someone who has this achievement.

Uplift Reserve

H3: ODST: Complete Uplift Reserve.

Deference of Darkness

H3: ODST: Complete any level without activating VISR mode.

Two Places, Same Time

H3: ODST: I've got my eye on you, Marine.

Your Heresy Will Stay Your Feet

Halo: Reach: Kill the Elite Zealot before he can escape during Tip of the Spear.

Mind the Skill Gap

Halo: Reach: Observe the logo of a buttoned-up mining company.

Stick With It...A Little Longer

Play a multiplayer or co-op game at least 3 months after your first game.

The Guardians Are Coming

Get killed by the Guardians.

Protocol Dictates Action

Halo: Reach: Complete ONI: Sword Base.

Still Sharp

Halo: Reach: Beat the par score on ONI: Sword Base.

We're Just Getting Started

Halo: Reach: Complete Winter Contingency.

Standard Operating Brocedure

Complete any co-op level on Normal difficulty.

Brovershield

Complete any co-op level on Heroic difficulty.

Your Journey Begins

Complete a campaign mission or a match of multiplayer.

Just Getting Started

Kill 100 enemies or players.

I'm Sorry, Dave

Halo: Reach: Find the hidden binary signature.