Electrocute

Electrocute is a Lightning spell used by s in Diablo III, a rough equivalent to the classic spell Chain Lightning.

In-game
Electrocute rapidly releases lightning arcs, instantly hitting any target within 60 yards and within line of sight, dealing Lightning damage with every tick. Note that a single tick of damage occurs with two zaps, not one.

The target can be hit even if it is blocked by other enemies, but Electrocute cannot bypass walls and terrain. After it hits the first target, it jumps to another enemy within 20 yards of the previous target, dealing same damage, then jumping to the third victim, making a total of 2 jumps (3 enemies per cast). Cannot jump back to the initial target or to the target that has already been hit by this particular arc. Electrocute counts as a Signature Spell and therefore costs no Arcane Power to cast.

As Electrocute hits instantly, it is the most accurate basic spell, and can be considered to be the best for Arcane Power generation.

Hitting a ground will not extend the spell any further (making firing blind useless), and the lightning will not jump to nearby enemies. In return, placing LMB on the target and holding it will cause the Wizard to continuously cast Electrocute on that target, even if the cursor is no longer aimed at that enemy, until LMB is released.

Also note that since Electrocute instantly hits a designated location or enemy, and does not continue to move further, it does not count as a missile, and therefore bypasses Missile Dampening and Slow Time spheres.

Runes:

 * Chain Lightning: can jump up to 10 targets from a single cast.
 * Forked Lightning: damage type changes to Fire, and Critical Hits also release 4 charged bolts in random directions, each hitting for 44% damage as Fire and piercing through enemies.
 * Lightning Blast: changes the channeled lightning into a single missile which hits for 140% damage and pierces through enemies.
 * Surge of Power: each enemy hit awards 1 Arcane Power per tick.
 * Arc Lightning: increases damage to 310%, but lightning turns into a 20 yard long, 160 degree wide cone instead.

Non-rune enhancements:

 * Velvet Camaral (Legendary Wizard Hat): doubles the amount of enemies the Electrocute can jump to.
 * The Shame of Delsere (Legendary Belt): the spell is cast 50% faster and restores 9-12 Arcane Power on each cast.
 * Myken's Ball of Hate (Legendary Source): Electrocute chain jumps can hit enemies that have already been hit (including the initial target). Will have no effect if there is only one enemy in range.
 * Triumvirate (Legendary Source): casting Electrocute increases damage of Arcane Orb by 300-400% for 6 seconds, stacking up to 3 times, charges not consumed upon cast.
 * Fragment of Destiny (Legendary Wand): Your Signature Spells attack 50% faster and deal triple damage. You gain a Spectral buff whenever you land an attack with a Signature Spell. Hydras deal 25-30% increased damage for each Spectral stack. Max 10 stacks.
 * Simplicity's Strength (Legendary Gem): increases damage by 25% (+0.5% per rank) and heals the character for 4% of maximum Life per hit (rank 25 bonus).
 * Boyarsky's Chip (Legendary Gem): Taunts the first enemy hit for 2 seconds (rank 25 bonus).

Passives:

 * Prodigy: each cast restores 5 Arcane Power.

Development
Electrocute was a Storm spell in early development stages. It was introduced in the trailer for the Wizard, and subsequently detailed on the official website. A spiritual sister to Chain Lightning, Electrocute fires lightning from the Wizard's fingertips, electrocuting up to two of her enemies. It is a very fast spell, and if it strikes a critical hit it will stun opponents.

In a gameplay video at BlizzCon's Diablo III panel, the use of runes was demonstrated on Electrocute: a Multistrike Rune made Electrocute hit far more enemies, increasing its similarity to Chain Lightning, and a Lethality Rune caused it to create a Nova-like explosion when killing an enemy with the spell.

Prior to Patch 2.1, it was the only Signature spell that could not change the damage type.

Before patch 2.0.4., it was the most popular Arcane Power regeneration spell, as due to bug, it restored double the amount when combined with Prodigy.