Health Vial (Discontinued)

You can use the flask by right clicking with it in hand, or by putting it in the secondary hand and pressing the key (for default M) To refill the flask just sleep.

The flask appears in your inventory.

In addition, you can improve the amount of healing by creating the ring of life and equipping it.

You can level up the flask for extra use. You just have to find fragmented souls and put the jar in a brewing stand like this one in the image. (souls are dropped by enemies you defeat)