343 Industries has revealed four special armor permutations for the Halo 5: Guardians multiplayer beta (they'll also be unlocked for the final game in 2015 as well) that you unlock by earning Achievements in Halo: The Master Chief Collection. Get a 360-degree view of them in the video above, and here are their descriptions and unlock details:

MARK VI [GEN1]

Early high-res armor development. Materials not representative of final in-game model.

DESCRIPTION: Technically obsolete, the Mark VI [GEN1] Mjolnir armor maintains a legendary luster among Spartans and the general public.

HOW TO UNLOCK: Earn the “Your Journey Begins” Achievement in MCC (Unlocks Helmet & Armor)

MARK VI [GEN1] SCARRED

Early high-res armor development. Materials not representative of final in-game model.

DESCRIPTION: The Mark VI was able to remain functional until all of its triply-redundant auto-repair and bypass nodes failed.

HOW TO UNLOCK: Earn the “Cairo Stations” Achievement in MCC (Unlocks Helmet & Armor)

HELIOSKRILL

Early high-res armor development. Materials not representative of final in-game model.

DESCRIPTION: The HELIOSKRILL is a work of art crafted by a Sangheili prodigy inspired to test her skill against the best that humanity could muster.

HOW TO UNLOCK: Earn the “Legend” Achievement in MCC (Unlocks Helmet & Armor)

NIGHTFALL

Early high-res armor development. Materials not representative of final in-game model.

DESCRIPTION: Spartans with Marine experience prefer NIGHTFALL armor when stationed on inhospitable worlds, due to its best-of-class life support.

HOW TO UNLOCK: Watch the Halo: Nightfall Episode 1 Second Story (Unlocks Helmet)

HOW TO UNLOCK: Watch all 5 episodes of Halo: Nightfall (Unlocks Armor)

Finally, 343 wanted everyone to know that what you see here is "early high-res armor development. Materials [are] not representative of final in-game model." In other words, they'll look appropriately battle-scarred, worn, and/or dirty when they're done.

Be sure to take a look at the full list of Master Chief Collection's 4000 Achievement points if you haven't seen them already. We also invite you to stop by our ever-expanding IGN First hub page for this ongoing month of Halo: The Master Chief Collection, the one-stop shop for everything Halo-related that we did this month.

Ryan McCaffrey is IGN’s Executive Editor of Previews and Xbox Guru-in-Chief. Follow him on Twitter at @DMC_Ryan, on IGN, catch him on Podcast Unlocked, and drop-ship him Taylor Ham sandwiches from New Jersey whenever possible.