A Guide to Cross-Realm Technology

New Player Help and Guides
Legion Updates
I thought with a lot of complaints it was best to put this at the top for now. With the Legion pre-patch, Blizzard has introduced "sharding" into CRZ. The implementation so far has been quite buggy, with reports like phasing in and out rapidly, not being able to see people in their own group, or finding capital cities sparsely populated due to aggressive sharding.

Stormwind and Orgrimmar became CRZ-enabled with Legion, however this functionality has been removed for RP realms specifically. This also seems to extend to Elwynn Forest and Durotar. These areas still remain CRZ-enabled on non-RP realms.

With an update later in 7.0.3, it seems that Class Halls and most of the Broken Isles have become CRZ-enabled as well. This was originally called an accident by Blue posts, however in a recent Q&A with Ion it is confirmed to be intentional.


So if you are experiencing any of the above issues, or just want to complain about CRZ in general, I recommend that you send in bug reports/feedback to Blizzard instead of posting it here. Give the representatives as much information as possible so that Blizzard can continue to improve this feature.

World of Warcraft today is a very different MMO than many remember so fondly. Blizzard has made several changes to the game over the years that encourage inclusiveness and accessibility for its wide playerbase so that they get an equal opportunity. One of the largest and most noticeable changes was introduced in the Mists of Pandaria Pre-Patch, in which Blizzard introduced CRZ, or Cross-Realm Zones, to most of the game world. But how exactly does that work? Can we play with friends on another realm? Join their guild? Does our realm even matter now? I see these questions asked a lot by players new and old, so let's dive into not just cross-realm zones, but cross-realm technology across the game in general, including subjects like Connected Realms and Battlegroups.

"What is a Cross-Realm Zone?"
A cross-realm zone (or CRZ, also used as a verb) is a zone that grabs players from a pool of specific realms in order to populate the area and make it feel more lively. You will notice these "foreign" players because they will have a (*) beside their name, and they may also have a realm suffix. Building on to CRZ, new to 7.0.3 are Shards, which are separate instances of these cross-realm zones that have been created on-the-fly to maintain stability if the zone is hosting too many players. Both of these processes should be entirely seamless and almost unnoticeable.

You cannot choose if you want to CRZ or not, and it's going to happen in most of the game world regardless of you realm's population size. Even Stormwind, Orgrimmar and new expansion content were recently included; areas that historically have not allowed CRZ. There are some exceptions, though.

- Stormwind, Orgrimmar, Elwynn Forest, and Durotar are CRZ-disabled on RP realms only
- The old world PVP zones of Wintergrasp and Tol'Borad do not allow CRZ
- Legion Dalaran's upper city seems to not show any CRZ, though the Underbelly does.

With most of the CRZ world being unavoidable, there are some viable concerns, like competition for resources, rare mobs, quest completion, and WPVP faction balance, among others. Blizzard has recently addressed the resource issue by making herb/ore nodes shared among players. Skinning and fishing were unaffected. They've also allowed quest mobs to be tagged by multiple players on the same faction. They may still be faction-tagged, however. (Need confirmation on that).

So there are a few questions that can come from this, but those details perhaps deserve their own quote boxes.

CTRL+F Directory:
Search "XPLAY" to learn about what content is available cross-realm, as well the limitations to how you can interact with players on another realm.
Search "CRC" to learn about Connected Realms, or merged/coalesced/joined realms.
Search "XREALMS" to learn about who is pooled together to make a cross-realm zone.
Search "XGROUPS" to learn about how cross-realm zones and instances are hosted by different servers.
Search "XQUEUES" to see me talk about matchmaking and battlegroups but probably not learn anything.
"What can you do with players on another realm?"
Almost all content in the game is now cross-realm. As of 7.0.3, players across all subregions can now join each other out in the world and inside of instanced content. You can chat, duel, group, dungeon, raid, and PVP with anybody on any realm. This does not only apply to players on your friends list, but anyone you happen to meet in the game. All players are also in the same matchmaking queue for random instances.

Keep in mind there is still a faction barrier, though the BattleTag/Real ID system trascends this and allows you to privately chat with friends on the opposite side.

The list of things you cannot do across realms is actually much smaller. That would be,

1) You cannot join the same guilds. These are tied to your realm.

2) You cannot trade items or gold, or send them mail. There are some specific exceptions: Conjured items like Mage food or Warlock healthstones can be traded cross-realm, and special dungeon loot can be traded with players in your group for a limited time. Those loot items will be marked as tradeable in their tooltips.

3) You cannot access another realm's auction house. These are also a part of your realm. It is worth noting that Alliance and Horde auction houses have been merged, and there is no longer a neutral AH.

4) Assuming Legion handles Mythic Raiding the same as WoD, you will not be able to do cross-realm Mythic Raids until the next tier is released, or the current tier has been nerfed. Mythic HFC has been cross-realm since 6.2.3.

So the main advantage of being on the same realm with your friends, then, is to share resources and be in the same guild.

"But Scutshakes ... I seem to be in a guild from another realm, how do you explain that?"
Well, Blizzard decided to do something else throughout Mists of Pandaria, and that was merge smaller realms together to create Connected Realms.

Connected Realms (not to be confused with Cross-Realm Groups, which are just parties of players from different realms) are clusters of 2-6 realms that function as a single realm. All players in the cluster can trade, join the same guilds, access the same auction house, etc. It's just like one realm. If Blizzard streamlined all of the realms in a cluster under one realm name, that would cause issues with players and guilds losing their unique names if somebody else in the cluster also had that name. To avoid the issue, each realm in the cluster still has all of its original characters and guilds. The only difference is that you now have a realm suffix attached to your character and guild name to prevent confusion. Nothing will have happened to your character, your belongings, your friends list, guild, etc. when these realms merged. This also means that you can bypass the limit of 12 characters per realm when you are a part of a cluster, but there is still an account-wide 50 character limit.

For example, the realms Black Dragonflight, Gul'dan, and Skullcrusher have all been merged together. You might have a character named "Blahblahblah-BlackDragonflight", and there might be someone else with a "Blahblahblah-Skullcrusher", and you both might be in the guild "Fuzzy Butt Monkeys-Gul'dan" together.

To my knowledge, it is not particularly well conveyed in-game that you are on a Connected Realm. Or at all, really. This has confused some people as to the nature of cross-realm interaction because they do not know they are merged with anyone!

To find out what realms are Connected, use this page
"Who will I see out in the world?"
There are a number of layers to determine your CRZ pool.

1) Each datacenter has its own CRZ pool. The current datacenters on the NA client are West Coast (Los Angeles, CA), Central (Chicago, IL. Includes Latin and Brazilian realms), and, most recently, Oceanic/SEA (Sydney, Australia). Players on a realm in Chicago will not naturally see players from a realm in LA.

2) Each subregion in the NA region (US, Latin, Brazil, Oceania) has its own pool. Brazil realms are based in the Chicago datacenter, but will only see players from other Brazilian realms.

3) Each realm type has its own pool. PVE will only CRZ with PVE. Same with PVP. RP-PVE and RP-PVP are also separate types.

4) There is a stated rule saying that realms farther than three time zones apart cannot CRZ, however the above rules should already cover that in most cases.

5) Anybody that is in a cross-realm group can be pulled to another datacenter, subregion, and realm type, depending on what server hosts that zone or instance. This should account for any exceptions you notice. This will also be explained later.

So, for example, if you are on Stormrage, as an American Normal-PVE realm on Chicago servers you will only CRZ with other American Normal-PVE realms on Chicago servers, unless of course somebody has been pulled into this CRZ pool from a group.

This means that players in the Brazil, Latin, and Oceanic regions will have a smaller world population because they have very few realms. There is even one realm that doesn't CRZ at all because it is the only one of its kind: Quel'Thalas, the only Latin PVE realm.

You can find where your realm is located with this link.


"If all these people are from different realms, then whose server will we play on? What happens when we group up?"
Cross-realm zones and cross-realm instances can be hosted on any realm, however the method to determine this is different between the two.

In the past, once a group's realm flag was decided, it was applied universally to the game world. When 7.0.3 launched, there seems to have been some changes in how zone hosting is decided, probably to combat exploitive/annoying realm hoppers. Realm flags are now decided on a zone-by-zone basis. The rules below are what I have observed with some testing, but feel free to propose different ideas.

- By default (in no group), every zone you enter will be hosted on your servers. Seeing as how cross-realm players will see the same rare mobs and resource nodes as you, it is assumed that this is not necessarily your home realm, but a phase hosted on the servers for your own CRZ pool. So keep that in mind when I say "flagged for your realm"; I mean more specifically "flagged for the phase that your home realm belongs to".

- In a group, the first time any member enters a zone, that zone is flagged by that player's realm, and thus is hosted by the datacenter it is on. Everybody else in the group who enters the zone while it is flagged will be phased to that realm's version of the zone.
-- This is when players are "pulled" to different CRZ pools. They are subject to latency changes if it is on one of the other two datacenters and may be flagged for PVP in a contested area on a PVP realm.
--- This does not mean you "change" realms per se. You are still based on your home realm, you are just connecting to another, and all of the limitations still apply (like no trading).
-- In the case of two or more players being in the same zone at the time of the group's formation, the group leader is the "first" and will flag the zone for his or her realm.

- Once this realm-flagged zone is vacated by all group members, a timer will start, which lasts about 15-20 minutes. Once it is up, the realm flag is removed, and the zone may be flagged once again when a group member re-enters the zone.
-- Re-entering the zone before this timer is up will stop and reset it.
-- Leaving the group does not seem to change anything, but making/joining a new group will reset realm flags for you specifically.

As for instances, they will be hosted by a much simpler method. The group leader's realm. If the group leader is Oceanic, then the rest of the group will connect to the datacenters in Sydney, complete with all the high ping if you're an American. Since PVP has two group leaders, the Americans will have a priority. If one side is American and one side is Oceanic, the instance will be hosted on American servers.
"Do Battlegroups matter anymore?" Or, "I think this is how Matchmaking works..."
Battlegroups are a subdivision of datacenters, and most of them comprise 20-50 different realms, though some may be smaller. In the past, your battlegroup determined who you would be able to group up with for instanced content, but over time Blizzard merged battlegroups and expanded matchmaking until they reached a point where battlegroups have become a shell of their former function.

Now when you queue for a random instance, the servers will first try to match you locally before matching you with players game-wide. The exact process I am not so sure about. There are a number of old community posts that share a matchmaking priority of Realm>Battlegroup>Datacenter>Region. That'd be nice if I still saw it parroted today, but since then there have been some changes to battlegroups and datacenters.

It is difficult to find official info on Battlegroups and matchmaking these days, but the most recent one I found was when the Oceanic datacenter was established. The most commonly accepted opinion today is that battlegroups don't matter anymore. That may be true, but they still are doing something anyway.

10/23/2014 03:15 AMPosted by Watcher

Q: Will I have to wait longer when attempting to find dungeons, raids and PvP?
A: When using “Looking For Raid” and “Looking For Dungeon”, players on Oceanic realms will remain in the same pools as players from North American realms, which should result in minimal changes to current wait times.
For PvP, the game will first try to match players on Oceanic realms for Unrated Battlegrounds with other players from their battlegroup. If successful, these groups should be placed on Australian servers. If two teams from within the battlegroup cannot be found, the groups are then made from the broader player pool and are likely to be placed on game servers located on the U.S. West Coast.
For Arena teams and Rated Battlegrounds, Oceanic versus Oceanic matches should take place on Australian servers. Oceanic versus North American matches may take place on servers located on the U.S. West Coast. Whether a team is designated Oceanic or North American is determined by the group leader’s realm.

For reference this was right before Warlords of Draenor.

This post is up to some interpretation, given Blizzard's sometimes fuzzy wording. But taking it for its word, it A) Supports that all subregions are in the same queue together, B) Confirms that battlegroups are still a part of matchmaking, C) Implies that Oceanic realms have a preference to match with LA battlegroups for latency.

If you interpret it simply as a fancy way of saying "Don't worry, you're still going to be able to group up with Americans, but we are trying to match you locally first.", then Realm>Battlegroup>Datacenter>Region may still very well be correct. It may or may not be simpler or more detailed than that.

If somebody could swoop in and clear things up that'd be pretty okay.

You can still find the different battlegroups listed here.

Reserved again just in case
Prepare for quality of graphics.
This note is about ; Ping time or ms.
When Legion was announced. I noted that you needed a level 70 in order to make the new Demon Hunter.
I selected several servers by CRZ and connected server stasis. Before the pre-patch the graphics were fine on my Laptop , but after the patch not so good. I logged into each one and wrote down the "ping home/world ", most of my leveled 70's had pings at 125/145ms. I also noted the FPS on them. Starting out at 70-90fps quickly running down a road and then noted that FPS went to 10-20fps.
I do have one out of the servers that stay high on fps and has a ping of around 70ms and holds at around 60 fps.
I also have 5-6 servers at 32-45ms/45ms and fps at around 60-90fps constantly good quality. My next move is to go to a CRZ area and check the FPS and check for Lag spikes.
My main server Ysera is in the 30/35ms with sometimes well over 150fps, but normally 90fps.
You as a new user considering a server selection.
My suggestion would be starting a Worgen and not taking the first quest, just turn and run around note the ping times and FPS. Look for details like is it raining there or how when you turn is it just bury or smother than expected?
This is only if you want the best that you can get. A higher pop server with be affected more than a lower pop server.
Have fun.
Recommend this replace Blindsight's how to choose a server guide in the sticky list.
Guide has been updated for Legion

- Broken Isles & Class Halls are now CRZ-enabled
- Stormwind, Orgrimmar, Elwynn Forest, and Durotar seem to be CRZ-disabled on RP realms only
Thanks for this. Just coming back to the game clueless about all these crz, sharding, and connected realm details. Was quite surprised to see a ton of people everywhere on my "dead" server on both factions. I'm assuming that the same applies to every zone including all legion content?

Your post answered most of the many questions I had. So basically, regardless of native population or faction balance the only difference between realms now is their economy because CRZ equals out everything else?

That's pretty darn awesome and saves me a lot of headache in trying to decide which toons to move since I currently have everything on what was once a dead realm... Basically, I don't think I have to move anything :O

To clarify a few minor things:
1) we can group up with anyone regardless of origin realm, right? And then queue for any content other than mythic raids?
2) I'm assuming that all CRZ people are in the same chat channels.
edit: how exactly does trade chat work? Is everyone in it or only the people from your realm/faction? I can see it being quite difficult to find trading partners from your realm if it's just one giant cluster of ineligible people.
edit2: is crz general chat (/1) linked across all cities like trade chat is? I hope so.

3) Do people from other realms randomly phase in and out or do they stay in the CRZ until they log out or something? For instance, if I'm in a group or chatting with someone, they won't just randomly disappear forever?
The CRZ system does make some attempt to consistently put people from the same realms into the same instances of a zone but the mechanic where new zone instances are created when existing instances get full also comes into play.

You see this most frequently after all realms are restarted. When players log in after restarts, there may be only one or two instances of a zone initially available so players from all realms may go into those instances until they get filled up and new zone instances are created for them. Overtime, however as people log off and back on, players get placed in currently active zone instances with other players from their realm.

The longer the time period since the realms were rebooted, the more likely you are to see the same players.

Sharding also comes into play for highly populated areas of a zone where what is essential an area instance, instead of a full zone instance is created to deal with high population density in the area. You see sharding most often in org and SW but it also occurs within leveling zones. There have been situations where large guild meetings had some folks put into one shard, and some folks put into another one. People in the different shards could not see one another.
I like how my friend who plays on Tichondrius likes to say that I play on a bad server because he has "popular" players and guilds on his server. Even tho my server has 0% down rate on expansion and patch releases. What is bad server?

Join the Conversation

Return to Forum