Makeshift Grappling Hook, which will be used to grapple around several points in Naxxramas. To create a grappling hook, you need to collect a few materials around Naxxramas:

Faerlina's Sewing Kit - As the name says, it's a drop from Grand Widow Faerlina.
Construct's Hook - Located in the second room of the Construct Quarter, by a vat of slime to the right.
Abomination's Chain - Chance to be fished from any slime in Naxxramas.

The Construct's Hook location in the Construct Quarter.

Once you have all three items, just combine them to create the

Makeshift Grappling Hook! Once you use the Grappling Hook, several grapple points will appear in certain areas of Naxxramas.

LOCATING ZACKETT SKULLSMASH

The next step is locating a goblin NPC, Zackett Skullsmash. This NPC is located on the rafters above Thaddius's room, and requires grappling through the room to reach. We have a video showing all the required steps to reach the NPC.

Once you reach the NPC, he will be "sleeping", bored of life. You can try poking at him, but that won't do much. To wake him up, toss a

Stratholme Holy Water on him. Once Zackett wakes up and berates you for it, he will give you a quest,

Inconvenience Fee, which requires you to collect the following:

20x Invader's Scourgestone, drops from bosses in Stratholme and Scholomance;
5x Corruptor's Scourgestone, drops from bosses in Naxxramas;
3x Dark Rune, drops from mobs in Scholomance and Corrin's Crossing, can be purchased from the Auction House
1x Black Coffee, sold by vendors in Shattrath/Stormwind/Dazar'alor, can be purchased from the Auction House.

Once you complete the quest, return to Zackett in Naxxramas and wake him up with another

Stratholme Holy Water. Once the quest is completed, Zackett will move to the central ring of Naxxramas, where he will start selling wares.

DEATH'S BARGAINING CHIPS

Once Zackett moves to the central ring of Naxxramas, he will start taking Scourgestones looted from Naxxramas, Stratholme and Scholomance in exchange for

Death's Bargaining Chip:

1x Corruptor's Scourgestone, dropped from bosses in Naxxramas, gives 1 Death's Bargaining Chip;
10x Invader's Scourgestone, dropped from bosses in Stratholme and Scholomance, gives 1 Death's Bargaining Chip.

Zackett has wares to sell for Death's Bargaining Chips:

Item	Cost	Description
Dented Raider's Helmet	3x Death's Bargaining Chip	Reveal a random Helm item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Helmet.
Dented Raider's Spaulders	3x Death's Bargaining Chip	Reveal a random Shoulder item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Spaulders.
Dented Raider's Chestpiece	3x Death's Bargaining Chip	Reveal a random Chest item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Chestpiece.
Dented Raider's Bracers	3x Death's Bargaining Chip	Reveal a random Bracers item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Bracers.
Dented Raider's Gauntlets	3x Death's Bargaining Chip	Reveal a random Gloves item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Gauntlets.
Dented Raider's Belt	3x Death's Bargaining Chip	Reveal a random Belt item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Belt.
Dented Raider's Leggings	3x Death's Bargaining Chip	Reveal a random Legs item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Leggings.
Dented Raider's Boots	3x Death's Bargaining Chip	Reveal a random Boots item from Kalimdor or Eastern Kingdoms. Chance to be Lamented Crusader's Boots.
Slime-Covered Scroll	12x Death's Bargaining Chip	Reveals a random Ancient Recipe from Naxxramas.
Phylacterweave	2,000	Used in crafting Tier 3 gear.
Plagued Grain	15x Death's Bargaining Chip	Toy that drops a plagued grain crate to the floor.
Rotten Delicious	30x Death's Bargaining Chip	Used in obtaining the Reins of Valiance mount.
Pattern: Cursed Cloth	20x Death's Bargaining Chip	Used in crafting Tier 3 Cloth gear. Requires the Feat of Strength Drop Dead, Gorgeous to see.
Pattern: Languished Leather	20x Death's Bargaining Chip	Used in crafting Tier 3 Leather gear. Requires the Feat of Strength Drop Dead, Gorgeous to see.
Pattern: Scourged Scales	20x Death's Bargaining Chip	Used in crafting Tier 3 Mail gear. Requires the Feat of Strength Drop Dead, Gorgeous to see.
Plans: Undeath Metal	20x Death's Bargaining Chip	Used in crafting Tier 3 Plate gear. Requires the Feat of Strength Drop Dead, Gorgeous to see.

SO HOW DO I CRAFT TIER 3?

Creating Tier 3 pieces requires a lot of gold, RNG and someone with an actual Tier 3 achievement! Here's what you need to do in order to craft a Tier 3 piece:

Loot a Lamented Crusader piece of gear from Zackett's Dented Gear tokens.
Repair the Lamented piece of gear by using one of the cursed Naxx items ( Cursed Cloth, Languished Leather, Scourged Scales, Undeath Metal). The recipes can only be obtained by someone who has the achievement Drop Dead, Gorgeous from collecting a full Tier 3 set, but you can work order for these if you don't have the achievement. This will turn the piece into a Desecrated piece of gear.
Once you have a Desecrated piece of gear, you can purify it by using Phylacterweave and Righteous Orb:
- Purify Helmet: 280 Phylacterweave, 10 Righteous Orb
- Purify Shoulders: 280 Phylacterweave, 10 Righteous Orb
- Purify Chestpiece: 210 Phylacterweave, 10 Righteous Orb
- Purify Bracers: 70 Phylacterweave, 10 Righteous Orb
- Purify Gauntlets: 140 Phylacterweave, 10 Righteous Orb
- Purify Belt: 70 Phylacterweave, 10 Righteous Orb
- Purify Leggings: 210 Phylacterweave, 10 Righteous Orb
- Purify Boots: 140 Phylacterweave, 10 Righteous Orb
- A complete set of Tier 3 armor will require 1400 Phylacterweave (or 2.8 million gold in vendor mats), 80 Righteous Orb.

Congratulations, you can now craft Tier 3 gear!