Life
Life is shown as a red orb in the lower left of the screen and will decrease as you receive damage. Characters die when they reach 0 life and must be resurrected in town. You can restore life by using flasks, gaining life regeneration from passive skills and equipment, or leeching life from enemies. Life is fully restored when you enter a town.
Every class starts out with 50 Life, and gains +12 per level giving a base life of 1238 at level 100. Strength increases Life, with every +10 node giving +5 Life. Characters do not begin with any life regeneration, but it is available from gear and passive skills.
New Formula for Forsaken Masters:
Maximum Life = (38 + (Level * 12) + (Strength / 2) + additive modifiers) * (100% + multiplicative modifiers)
Old Formula:
Maximum Life = (42 + (Level * 8) + (Strength / 2) + additive modifiers) * (100% + multiplicative modifiers)
Additive modifiers are added directly to your base life (+x to maximum life). Multiplicative modifiers apply to additive modifiers as well as base life and strength (+x% increased maximum life). See Modifiers.
Passive skills
There are passive skills that grant life bonuses.
Life
These passive skills grant increased maximum life or additional base maximum life.
Life gain on hit
When an enemy is hit by your attack, you gain an amount of life equal to combined life gain on hit bonuses from passives and all other sources. This applies to each enemy hit by your attacks, so a single attack that hits multiple targets can trigger more than one life gain on hit effect. Unlike life leech, life gained this way is restored instantly.
These passive skills grant additional life gained for each enemy hit by the character's attacks.
Life gain on kill
When an enemy is killed by your attack, you gain an amount of life equal to combined life gain on killing blow bonuses from passives and all other sources. This effect triggers once for each enemy killed. Unlike life leech, life gained this way is restored instantly.
These passive skills grant additional life gained when the character kills an enemy.
Miscellany
These passive skills are related to life, but do not fit into any other category.