Death's Bargaining Chip

Death's Bargaining Chip is a reward from Zackett Skullsmash's repeatable quests after waking him up in [1-70] Inconvenience Fee after unlocking ancient Secrets of Naxxramas via the [Wards of the Dread Citadel] achievement:

Zackett then turns around and uses those chips to unlock Tier 3 craftables, among a few other items:

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]