Shielding

Shielded and Plagued Dune Dervish.

Shielding is a Boss Modifier that may appear on Champions or Bosses (but not boss minions) in Diablo III.

Shielding causes a shielding bubble to appear around the Champion, boss, or boss' minion for a few seconds, every few seconds. The shield grants immunity to all forms of damage and reduces or deflects many CC effects as well, for the duration of its presence. Monsters can not be hurt in any way while shielded, though they can still be slowed by rooting effects.

Shielding is identical in function to the Invulnerable Minions effect, except that one only appears on boss minions, and is permanent. Shielding pops in and out on Bosses and Champions, turning on for a few seconds, then vanishing again without warning or any set on/off time.

Shielding can be seen on some Elites, though Magda is the only commonly-seen Elite with the property. Her Shielding functions the same as shields do on random enemies, but the on/off of the shield seems to be set to her hit points rather than a semi-random timer. Her shield turns on with about 75%, 50%, and 25% of hit points.

Shielding

• Monster Level Minimum: 31 (Nightmare and later)
• Available to: Champions and bosses, but not boss minions.
• Damage Type: n/a
• Additional Resistances: n/a
• Can Not Spawn With: Avenger, Extra Health, Health Link, Horde, Illusionist, Invulnerable Minions, Missile Dampening, Vampiric.

Strategy

Shielded monsters can not be damaged, so players should learn to recognize the effect and not waste time attacking a monster while it's invulnerable. As is often the case, this modifier is more dangerous when found on Champions, since all of them have it. Bosses and their minions get shielding, but it seems to be less frequent, especially on the minions.

Slowing effects that rely on hitting the enemy, such as Entangling Shot, or stunning attacks like Seismic Slam are generally ineffective against shielded enemies. Area effects like Caltrops may still work though, so adjust your tactics accordingly.

It seems that Shielding can not pair with Shielded Minions on the same boss and his pack; at least it's not yet been reported by any players.

Media

The Shielding bubble has a greenish-tint and is instantly recognizable when in effect on a monster. Boss minions will also gain a shield at times, and their tooltip shows "Shielding Minion" whether the shield is active or not.

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  Protection for a puking zombie.

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  Unshielded Dune Dervish minion.

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  Shielding Vortex, Jailer gets pounded by a group.

A Barbarian struggles against a Shielded boss in v1.0.3, when the shield "up time" was buggy and much too frequent.

A party teams up against a Vortex, Shielding, Jailer boss in Act 4, Hell.