Invisibility (mechanic)

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Using invisibility

There are only a few items in the game that provide invisibility. They are: [Lesser Invisibility Potion] (requires level 23 to use; lasts 15 seconds with a 10-minute cooldown), [Invisibility Potion] (requires level 37 to use; lasts 18 seconds with a 10-minute cooldown), and [Gnomish Cloaking Device] (requires 200 Engineering to use; lasts 10 seconds with a 1-hour cooldown).

Just like Stealth, invisibility comes undone if you take most actions other than movement (however, it breaks after finishing a cast). This does not necessarily apply to mobs, some remain invisible when attacked. Unlike Stealth your movement speed is unaffected while invisible.

Invisible mobs

There are several invisible mobs in the world. There are the ghosts in the Ruins of Lordaeron in Tirisfal Glades, the ghosts in Raven Hill in Duskwood, and the infamous invisible patrols in Dire Maul West.

Then there are the dangerous Elite Ambushers in the Silithus Hive Ashi and Hive Zora, the Eyeless Watchers in the 3 main encampments in the Eastern Plaguelands and of course the Stratholme Eye of Naxxramas.

Other than the Dire Maul, Silithus and Eastern Plagueland ones, however, the most invisible mobs of the world tend to be neutral, and won't attack unless provoked, which means that you wouldn't know they were there unless you had invisibility detection magic or happen to hit them with an AoE (in which case they will engage you, but remain invisible).

Invisibility detection

Unlike [Stealth], there is no chance to detect an invisible target without a detection effect. However, detection effects reveal invisible units at any range. Even when detected, invisible units are transparent and do not display a name tag.

There are items and spells in the game that provide the ability to see invisible beings. Prior to WoW 2.0, there were three separate grades of invisibility, but currently there is only one. Likewise, Warlocks previously had three Detect Invisibility spells, but currently there is only the one: Detect Invisibility, acquired at level 26. This buff can be cast on any ally, not just the Warlock, and lasts 10 minutes.

Items that provide invisibility detection include: [Elixir of Detect Lesser Invisibility] (requires level 29 to use; lasts 10 minutes).

Mobs with invisibility detection

Each of the major cities has patrolling guards with Stealth and invisibility detection abilities, and some mobs in instances (some were added to Stratholme in patch 1.6, for example) can also detect some grade of invisibility.

Tables of invisibility and detection

This section concerns content related to The Burning Crusade.

Invisibility Level	Duration	Source
100	5 min	Template:Class Icon Warlock SmallSuccubus' Lesser Invisibility
100	15 sec	[Lesser Invisibility Potion]
200	10 sec	[Gnomish Cloaking Device]
200	18 sec	[Invisibility Potion]
200	5 min	[Enchanted Moonstalker Cloak]
340	20 sec	Template:Class Icon Mage SmallInvisibility

Detection Level	Duration	Source
100	10 min	[Elixir of Detect Lesser Invisibility]
100	10 min	Pre-BC Template:Class Icon Warlock SmallDetect Lesser Invisibility
200	10 min	Pre-BC Template:Class Icon Warlock SmallDetect Invisibility
300	10 min	Pre-BC Template:Class Icon Warlock SmallDetect Greater Invisibility
1000	20 sec	Template:Class Icon Mage SmallInvisibility
1000	10 min	Template:Class Icon Warlock SmallDetect Invisibility