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Battlegrounds are a special type of zone where unique player versus player
challenges can be found. They exist on both PvE and PvP servers, and provide
a level of competitive inter-faction play that can’t be found anywhere else.
Battlegrounds are special areas distinguished by a red instance portal. The
first time you encounter a battleground, you must walk through this red
portal to enter it, although later, you can journey there via flying mount if
you unlock the flight path there.
In a battleground, player versus player combat is always enabled, regardless
of server type. This gives players on the PvE server who want a taste of PvP
gameplay the ability to do so on more manageable terms.
While in a battlegrounds area, you can team up with friendly players while you
embark on quests designed to pit you against players of the opposing faction.
You can easily leave a battlegrounds area and return to the normal world by
speaking to another friendly battleground NPC.