Vortex

Vortex is a Boss Modifier in Diablo III that can be found on Champions and Bosses, but not boss minions. It enables the boss or champions to yank your hero right up to them, which can be very dangerous against hard-hitting melee attackers. It's even worse when facing a boss pack with Molten or Plagued or other AoE attacks, since the pull will bring a character right into the killing field, sometimes resulting in virtually instant death.

Vortex bosses want to get closer to you.

There is no hit % chance on Vortex, and monsters cast it periodically, generally every 15 or 20 seconds, though they may do so more or less often. Vortex can not be dodged or avoided or resisted, and surviving against it requires a player to be ready to react the instant the Vortex is cast, pulling them into danger.

Vortex:

• Monster Level Minimum: 15
• Available to: Champions and Bosses, but not boss minions.
• Damage Type: N/A.
• Additional Resistances: None.
• Can Not Spawn With: Knockback, Nightmarish or (as of the v1.0.4 patch[1]) Jailer.

Strategy

As when dealing with a Teleporter boss, it's essential to remain ready for instant action. Do not spend all of your resource while at a safe distance, and make sure at least one of your panic button skills is available for instant use, if the Vortex sucks you in. Vortex is very dangerous, but it's seldom used twice in succession, so if you get away you should be safe for at least a few seconds, which will ideally be long enough for your cooldowns to count off and your defensive skills to become available again.

While melee characters might not be bothered by this effect at all, it's very dangerous for ranged attackers. Even melee characters can fear it though, against hard-hitting enemies or bosses with other deadly AoE effects, such as Molten or Fire Chains or Plagued.

There seems to be a maximum distance outside of which Vortex will not work; character who remain off the screen are very seldom Vortexed in, and it's a pull, not a warp, so geographical features such as walls and other obstacles might stop the pull before a character is yanked right next to the enemy.

The effect can actually work against the AI of some ranged attacker bosses, who will stop attacking and attempt to retreat when the Vortex triggers and they suddenly find a character in close proximity.

Development

Vortex sequence. The blue flash is when the skeleton casts Vortex, and the white streak is the Wizard (with Diamond Skin active) being yanked back into range.

Vortex was first seen by players in the Blizzcon 2010 demo. The effect was shocking and quite effective, but the lack of any sort of graphics to demonstrate the effect was confusing. Players thought perhaps they'd lagged out or had a moment of rubber banding. As Julian Love confirmed[2] at the time, this was a known issue, as the modifier was newly-added to the game and not yet polished.

Once the graphical effect was added the player confusion was abated, at least after a new player sees the effect a few times.

Media

Vortex does not change the appearance of the boss, so it can only be observed in the tooltip hover text. Or by the effect of the ability, as it yanks your character into danger.

There is a visual for the ability; the boss or champion using the Vortex makes a quick casting animation while glowing with a blue-white light, just before the effect takes place. It's unlikely many players notice the flash of light .3 seconds before they are hauled back to the monster, but it does occur as you can see with close attention to the videos of the boss encounter.

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  Horde Vortex Teleporter with big melee damage = doom.

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  One of the nastiest bosses you'll ever see in Act One.

A wizard battles a boss skeleton and his pack with Vortex, Waller, Electrified, and Invulnerable Minions.

Fallen with Vortex, Arcane Enchanted, and more.