Wards of the Dread Citadel

Wards of the Dread Citadel is a dungeon & raid achievement earned by empowering the [Argent Dawn Commission] to unlock secrets within Naxxramas. Players must have already unlocked access to the Legacy of Scholomance via the [Memory of Scholomance] achievement in order to progress on this achievement.

Walkthrough

The Scourge crystal in Stratholme

Unlock access to the Legacy of Scholomance.
If not already in possession of a pre-Cataclysm completed [Argent Dawn Commission] or its upgrades, enter the Legacy of Scholomance and head to the Great Ossuary with Rattlegore. Find a [Cracked Argent Dawn Commission] atop the first pile on the left and repair it with a [Righteous Orb] and 4x [Truesilver Bar].
Equip the trinket, head back to the Legacy of Scholomance, then kill Darkmaster Gandling to loot [Darkmaster's Scourgestone] and complete [1-70] Darkmaster's Scourgestone. The quest can be turned in to three NPCs across Lordaeron, but Duke Nicholas Zverenhoff at Light's Hope Chapel is the closest to the next objective. This unlocks [Invader's Scourgestone] collection.
Enter Stratholme Main Gate, then clear a path northwest toward Crusaders' Square with the Argent Dawn Commission equipped. Do not cross the Festival Lane gate into the eastern side of Stratholme. On the way, find and kill an Eye of Naxxramas, then loot the [Ward of Naxxramas] from its corpse. The shade spawns with a yell: The living are here!
Loot a [Stratholme Holy Water] from any Stratholme Supply Crate, then head to Crusaders' Square and turn south toward the southern gate.
Use the Ward to gain a two-minute Truesight buff. A portal with a Scourge crystal in it appears at ^{[38.7, 40.9]} immediately in front of the gate. Throw the holy water into it, which alerts the Hand of Naxxramas: The living? Here?! This starts a five-minute timer, tracked by a debuff: Sleight of Hand.
Quickly run east through the Festival Lane at ^[89, 32] and open the gate to the Service side.
Speed run the Stratholme Service Entrance side before that timer runs out:
1. Defeat the three bosses in front of ziggurats in the Gauntlet at ^[57, 45], ^[75, 46], ^[67, 24] and kill all the Thuzadin Acolytes within them to destroy the the Ash'ari Crystals
2. Kill all nine abominations around ^[47, 20] in the Slaughter Square
3. Defeat Ramstein the Gorger at ^[42, 20] when it runs out from the Slaughter House
4. Kill all the Mindless Undead that stream out from the southern path at ^[43, 30]. It may be necessary to run east toward the gate at ^[50, 20] to trigger them
5. Kill the Black Guard Sentries at ^[41, 20] to gain entry to Rivendare's room in the Slaughter House
6. Kill Aurius Rivendare at ^[38, 20]
7. Exit the slaughterhouse, run south toward the tunnel with the portal barred with a portcullis, then use the To Dust extra action button that appears at ^[42, 35]:
  To Dust — Unleash a torrential blast of holy light to smite the Hand of Naxxramas. 3 sec cast

Stratholme

If done correctly, the following message appears:

As the Hand of Naxxramas burns into a pile of ash, it is clear that recent events have escalated such that someone should be made aware of them.

Exit the dungeon and find Archmage Angela Dosantos at ^{[75.5, 52.8]} by the entrance to Tyr's Hand (or at Light's Hope Chapel) and speak with her:

Archmage Angela Dosantos

Scourgestones? Fleeing shades? Murder mysteries in Caer Darrow?

While I appreciate your sense of urgency in a time seemingly so dire, I assure you that neither Kel'Thuzad nor the Lich King himself are of any threat to us now.

I do admire your creativity and commitment to this story. If there is a shred of truth to what you are saying, I may be able to help you.

Depending on the player's standing with the Argent Dawn, she offers one of one of three quests:

[1-70] The Dread Citadel - Naxxramas (honored)
[1-70] The Dread Citadel - Naxxramas (revered)
[1-70] The Dread Citadel - Naxxramas (exalted)

If Argent Dawn reputation is below Honored, doing the Eastern Plaguelands storyline with Fiona's Caravan through [15-30] Argent Call: The Trial of the Crypt will quickly gain standing with the faction.

Unlocks

Revealed Portal to Naxxramas

Completing any of the three quests awards the account-wide Wards of the Dread Citadel achievement. This unlocks the Revealed Portal to Naxxramas at ^{[35.7, 22.9]} in the Plaguewood that teleports the player to Naxxramas, but now with new secrets. Unlike the Legacy of Scholomance, this is not a separate instance but a permanent modification to Naxxramas; these secrets are also present when accessing Naxxramas from its normal entrance at ^{[87.3, 50.9]} above the Carrion Fields in the Dragonblight.

Additionally, as players zone into appropriate instances, they will gain the Empowered Argent Dawn Commission buff, allowing them to loot scourgestones without having to equip the trinket:

Empowered Argent Dawn Commission — Allows for the acquisition of Scourgestones on behalf of the Argent Dawn.

Trash mobs in Naxxramas will drop [Wartorn Scrap], bosses will drop a [Corruptor's Scourgestone], and [Frozen Rune] objects can be found all over the raid.

Zackett Skullsmash and the Portal to Eastern Plaguelands inside Naxxramas

Although the secret to unlocking special access to Naxxramas is done, the hunt for more secrets continues. The key item and NPC for obtaining new rewards and achievements are the [Makeshift Grappling Hook] and Zackett Skullsmash ( [1-70] Inconvenience Fee). Notable secrets and rewards are [Reins of Valiance], various Tier 3 and Frost Resist recipes, as well as achievements [Putting Wilhelm Out of Business] ( [Omarion's Second Handbook]) and [Never Bothered, Anyway].

Ancient recipes

These non-bound recipes are randomly contained in the [Slime-Covered Scroll]:

Vendor

Zackett Skullsmash
Item	Cost	Type
[Dented Raider's Helmet]	3	Old transmog or [Lamented Crusader's Helmet]
[Dented Raider's Spaulders]	3	Old transmog or [Lamented Crusader's Spaulders]
[Dented Raider's Chestpiece]	3	Old transmog or [Lamented Crusader's Chestpiece]
[Dented Raider's Bracers]	3	Old transmog or [Lamented Crusader's Bracers]
[Dented Raider's Gauntlets]	3	Old transmog or [Lamented Crusader's Gauntlets]
[Dented Raider's Belt]	3	Old transmog or [Lamented Crusader's Belt]
[Dented Raider's Leggings]	3	Old transmog or [Lamented Crusader's Leggings]
[Dented Raider's Boots]	3	Old transmog or [Lamented Crusader's Boots]
[Slime-Covered Scroll]	12	Non-BoP ancient recipes
[Phylacterweave]	2,000	Tier 3 crafting reagent
[Plagued Grain]	15	Toy
[Rotten Delicious]	30	For [Reins of Valiance]
[Pattern: Cursed Cloth]	20 ^†	Tier 3 cloth reagent - [Cursed Cloth]
[Pattern: Languished Leather]	20 ^†	Tier 3 leather reagent - [Languished Leather]
[Pattern: Scourged Scales]	20 ^†	Tier 3 mail reagent - [Scourged Scales]
[Plans: Undeath Metal]	20 ^†	Tier 3 plate reagent - [Undeath Metal]