Lifesteal is an alternative form of Healing and a typical ability of Dark Heroes. The healing is based on the damage dealt. This means that the more damage the hero deals, the more hit points they get back.
Heroes who deal a lot of damage benefit most from Lifesteal. The obvious disadvantage of Lifesteal is, of course, that no healing is possible if the hero cannot deal damage. Reasons can be shields like Invincibility on the target, or the hero is Diseased or not able to attack at all. For example if he or she is Frozen.
The effect of Lifesteal is easy to recognize by a "swarm of green +", which floats back from the hit enemy to the attacker.
Vampiric Runes can also give heroes who do not have a natural Lifesteal trait this effect. These Runes return up to 10% of the damage caused to the wearer of the rune as hit points with every hit. The percentage values of several Runes and natural Lifesteal stacks; in other words, the percentage values are added together.
Soulless Scourge (Trait): Immune to Poison, Venom, Wound, and Disease. Lifesteals 25% of damage dealt. Immortality Through Death (Trait): Self and Undead allies Lifesteal 25% more damage and gain Foresight at the start of every turn.
Siphoning Slice (Special Attack): Melee Spirit attack in which a % of the damage dealt returns as Lifesteal for the team. Soulless Scourge (Trait): Immune to Poison, Venom, Wound, and Disease. Lifesteals 25% of damage dealt.