Simulacrum

Simulacrum is a Blood and Bone skill in Diablo III.

In-game
When cast, creates a bloody entity (visually, a skinless human body) that will, without any additional cost, duplicate any Essence-spending skills (Secondary skills: Death Nova,, Skeletal Mage) at any nearby target of its choice. They only duplicate the actual casts by the character, do not make casts of their own, and thus cannot use a skill that the Necromancer does not have equipped.

For all purposes, these spells apply as if the Necromancer cast them, benefiting from enhancements, except for they spend no resources. However, the spell also comes at a considerable cost of quarter of the character's maximum Life.

Any effect that would increase minion damage will only apply to the Simulacrum's own attacks: its spells are only enhanced if the Necromancer's own are.

The Simulacrum will follow the Necromancer around, and will attack on its own (with a one-handed scythe), but can be attacked by enemies too (though it also blocks pathing).

Skill Runes

 * Cursed Form: While active, makes all Curse skills apply all three curses to each target, even if the Necromancer does not have the other two Curses on their skill set. This does not cause the skills to be cast; instead, any enemy affected by one Curse automatically receives the effect of the other two.
 * Reservoir: While active, also increases maximum Essence by . When this effect is applied, the current Essence also increases so that its percentage remains the same.
 * Self Sacrifice: While Simulacrum is active, if the Necromancer suffers fatal damage, the Simulacrum is immediately destroyed and the Necromancer is healed to full Life without dying. This effect activates after all other life-saving effects are expended.
 * Blood Debt: Life costs for skills are reduced by of their original cost while Simulacrum is active. This does not apply to the Simulacrum itself.
 * Blood and Bone: Also creates the second Simulacrum of Bone, which will likewise duplicate spells (so each skill will be used 3 times at once), but the duration is reduced to seconds. Life cost does not change.

Non-rune enhancements

 * Haunted Visions (Legendary Amulet): Simulacrum drains 1% of the Necromancer's maximum Life every second, but lasts forever. Will no longer duplicate, instead duplicating.
 * Tasker and Theo (Legendary Gloves): Simulacrum attacks 40-50% faster.
 * Enforcer (Legendary Gem): increases damage by 15% (+0.3% per rank) and reduces damage taken by 90% (rank 25 bonus).
 * Gelmindor's Marrow Guards (Legendary Bracers): cast from Simulacrums deals 300-400% increased damage.
 * Bones of Rathma Set (Set Bonus for 2 items): Necromancer's minions reduce the remaining cooldown of Army of the Dead by 0.5 seconds each time they deal damage.
 * Bones of Rathma Set (Set Bonus for 4 items): Simulacrum become immune to damage. the Necromancer gains 1% damage reduction for 15 seconds each time their minions deal damage, stacking up tp 75 times.
 * Bones of Rathma Set (Set Bonus for 6 items): each permanent minion increases the damage of and Army of the Dead by 500%, up to 9000%.
 * Trag'Oul's Avatar Set (Set Bonus for 6 items): Simulacrum and its Blood skills (which would cost Life to Necromancer) deal 3800% increased damage. Healing from skills is increased by 100%.
 * Masquerade of Burning Carnival Set (Set Bonus for 2 items): Simulacrums no longer take damage, gain all runes, and its cooldown is refreshed on death.
 * Masquerade of Burning Carnival Set (Set Bonus for 4 items): while active, damage taken is reduced by 50%, and damage taken is split between the Necromancer and their Simulacrums.
 * Masquerade of Burning Carnival Set (Set Bonus for 6 items): cast by Simulacrums deals 6,000% increased damage (and same for normal casts).

Passives

 * Blood for Blood: removes the Life cost when picking up a Health Globe, storing up to 10 charges.
 * Rathma's Shield: for 4 seconds after casting Simulacrum, Land of the Dead or Army of the Dead, the Necromancer will lose no Life, both from attacks and from their own Blood skills, Simulacrum included (if cast after LotD or AotD).
 * Blood is Power: every 100% of maximum Life drained by Simulacrum will reduce all remaining cooldowns by 20%.
 * Aberrant Animator: grants 200% of the Necromancer's.
 * Stand Alone: grants 100% increased Armor. This bonus decreases by 10% (minimum 0) for each active minion.
 * Grisly Tribute: each attack made by the Simulacrum heals the Necromancer for 10% of their Life per Hit.

Trivia

 * This skill (with Self Sacrifice rune) is one of the two ways to be saved from dying by an active skill, the other being Prophet.