Newbie guide/Instanced Dungeons
Instanced dungeons
- Main article: Newbie instance guide
Group encounters
Instanced Dungeons (or "Instances") are where the fun really begins. These are not the sort of places you'll want to go alone. Unlike many areas of the game where you may easily get by as a solo player, instances and dungeons are designed to challenge groups of players. Most instances and dungeons will require five people to complete successfully. They always contain many Elite monsters.
Instances are a great way for groups to get experience and loot, though they present quite a challenge. It is ideal to construct well-balanced groups that include members which fill all party roles: typically a tank, a healer, and three damage dealers. Additionally, it is preferable to have at least one party member with good crowd control abilities.
There are four classes that can resurrect when out of combat: Priest, Druid, Paladin, and Shaman. In addition, the Druid ability 
[Rebirth], the Death Knight ability 
[Raise Ally], and the warlock ability 
[Soulstone] can resurrect players in combat. engineers of any class can make or buy 
[Goblin Jumper Cables], which allow the user to attempt to resurrect someone. Anyone in a maximum level guild will have the ability 
[Mass Resurrection], which will allow them to resurrect all dead players within a group.
See the class article for a table of roles that usually need to be played, and the rating of each class' ability to fulfill that role.
Instances are both sources of excitement, and of dread.
A place for you and your group only
In the open world, monsters exist and are free to roam. Anybody can come along, kill them, get the loot, skin them, etc. and move on. If one player kills a monster, obviously it can't be killed twice. That means other players have to wait until that monster respawns, which occurs regularly (usually within 5-15 minutes). Some monsters are quest targets, which need to be killed by any player attempting to complete a quest (a well-known example is Hogger for the quest 
[11E] Wanted: "Hogger" in Elwynn Forest). You may find yourself waiting for Hogger to respawn before you can kill him again. You may even be able to kill the same monster any number of times, as long as you wish to wait around.
In instances, it doesn't quite work the same way. Each group that goes into an instanced dungeon gets their own version of it – their own instance of it, hence the name. This means you will never be inconvenienced by another group going in and killing all of the monsters, getting the loot before you do, but you will also be completely responsible for your own safety. Each group gets to go through the whole instance on their own. This can result in good loot and experience as a group progresses through an instance.
Monsters in a dungeon do not typically respawn, unless a long period of time has passed, or a special scripted event is executed. For example, in the Deadmines in Westfall, the Goblins and Defias Miners (of various types) stay dead. The wandering Defias Enforcers and Taskmasters (patrols) are the only ones that respawn regularly (just to keep things interesting). Typically, dungeon respawns will not be much of a concern, unless you leave a dungeon in order to return later.
Death and resurrection in instances
If you die in an instance, your spirit need only find its way back to the entrance of it. As soon as you re-enter the instance, you are resurrected normally, but at the instance gate. This can mean that you may have a long way to run before you catch up to the rest of your group. In certain cases, you may end up fighting your way back to your group (or your group, if you're the only one left, may end up fighting their way back to you!). The benefit of this is that if every member of your group dies in a battle, you don't need to go walk around looking for your corpses. You just need to re-enter the instance, and everyone gets revived at the same point.
If your group has advanced a considerable distance into an instance, it may be desirable to avoid pulling mobs on the way back. It's smart to try to allow characters with resurrection abilities, such as priests, paladins, shaman, druids, or players in maximum level guilds with the spell [Mass Resurrection] to survive a difficult fight, even if other characters must sacrifice themselves in the process. If these particular characters survive a disaster that kills the rest of the party, they can eventually resurrect everyone else – preventing a long run back.