Estus Flask (Dark Souls)

Estus Flasks are a healing items in Dark Souls.

In-Game Description
''The Undead treasure these dull green flasks. Fill with Estus at bonfire. Fills HP. The Estus Flasks are linked to the Fire Keepers. The Dark Tales also make reference:''

An emerald flask, from the Keeper's soul/she lives to protect the flame,/and dies to protect it further.

Availability
Estus flasks are first granted to the player by Oscar. Oscar gives the player 5 estus before succumbing. Thereafter, players recieve up to 5 estus by resting at an unkindled bonfire. A kindled bonfire yields 10 estus; further kindling bonfires throug the Rite of Kindling rewards an additional 5 estus per kindle to up to 20 estus flasks in total.

Effect
Estus Flasks are the basic healing items in Dark Souls. They are replenished via resting at bonfires. The amount they heal can be upgraded by offering Firekeeper's Souls to other firekeepers to up to +7.

Backstory
Estus are fondly treasured by the undead. Oscar names it "an undead favorite". On the other hand, the living are not cordial about estus. The undead hunter Lloyd created Lloyd's Talismans to aid in his extermination of the undead.