Hearthshell is a piece of Demon Unique armor with no boss attached: it drops anywhere in Nightmare, most often from N7 up (rarer below that home difficulty, never above it), and nowhere else. Every copy is item level 100, and there 0.3% of what falls comes up Unique. It is built on Exalted Tortoiseshell Mail — step 6 of the Tortoiseshell Mail line, item level 80 and up.

It always rolls the same numbers: +96 Armor, +28 Ward, +436 Maximum Health, +99 Armor, +32 Ward, +187 Armor, +418 Maximum Health and +50% Healing Received.

One Unique drop in 40 is a Mythical copy: the same item carrying 15–25% Mythical Energy that boosts every stat on it and can never be changed; the 15% floor is 10 times as common as the perfect 25%.

On top of that it carries Hearthshell — +40% Maximum Health; +25 Healing Received.

“Warm, slow, and impossible to knock over.”