The Health Augmentation is one of the eight Augmentations from Fable and Fable: The Lost Chapters. It's a rare augmentation, since it has only appeared a few times, mainly in four swords, the Sword of Aeons, Avo's Tear, Solus Greatsword and The Bereaver (Fable TLC only) .
This regenerates Health continuously while the augmented weapon is assigned as your melee or ranged weapon. Bind this Augmentation to your Weapon through the Weapon Menu. Remember, this is permanent!
It can be bought from the weapon smiths in Bowerstone North (only one available) and Snowspire Village (restocks every 10 days). One can be found in a Silver Chest in Witchwood Stones.