Blizzard have written an extensive post going over all the issues the WotLK pre-patch events have been having, how they’re supposed to work, how they are being fixed, their original timings and more.

Issues and Clarifications (Source)

Hello!

We wanted to provide a quick update on the status of the Zombie Plague and Scourge Invasion pre-patch events, since there’s a lot of confusion floating around about how they are supposed to work and when specific events are supposed to fire. This is unsurprising considering how complex these events are. Apologies in advance as this post is going to be a pretty long one, but we felt it was important to be really detailed here with what’s happened, what is yet to happen, and how this differs from what you may have expected.

First, let’s break down exactly what the events look like in the 3.3.5 data which we are using for 3.4.0 Wrath of the Lich King Classic:

Day 0

Zombie Plague Stage 1 Begins – This involves Plague Crates appearing in Booty Bay and the plague kicks off.

Day 2

Zombie Plague Stage 2 Begins – Increased infection vectors move to all capital cities. Crates, Roaches, etc.

Day 3

Zombie Plague Stage 3 Begins – Increased intensity with it becoming easier to become infected.

When Zombie Plague Stage 3 begins the Scourge Invasions also begin and Necropli begin spawning in various zones in Eastern Kingdoms and Kalimdor.

Day 4

Zombie Plague Stage 4 Begins – Yet more increased intensity, the disease becomes harder to remove, etc.

Day 5

Zombie Plague Stage 5 Begins – Event winds down and effectively ends, but plague vermin and suspicious crates persist.

Day 10

The Plague Cure Event Begins – Professor Putress and plague cure quests become available.

Day 18

The Scourge Necropoli in the various Eastern Kingdoms and Kalimdor zones disappear and the epilogue events begin.

Plague Cure event ends

The Last Chapter/City Attacks begin – This is when the scourge begin attacking cities and the RP events with Thrall and Garrosh for the Horde, and Varian Wrynn for the Alliance kick off.

Day 21

All events end and the Expansion Launches.

All of the events listed above are on rigid timers, and are all meant to fire sequentially, meaning if the chain is broken for any of these events, it can impact the timing for all subsequent events. This, combined with a bit of human error led to a variety of issues and confusion over the weekend.

So, now that we’ve recapped how it was all set up in data, let’s examine some of the issues we had:

The Scourge Invasions started “early” – According to the data above, this is correct, but we had a miscommunication internally and a general misunderstanding of when this was supposed to begin and what triggered these events. As a result, the timing we communicated for the Scourge Invasions starting was incorrect. This was simple human error. Overall, we weren’t terribly concerned that these events started earlier than we had indicated, because it only meant more time to farm Necrotic Runes and other rewards.

The Zombie Plague ended “early” – in the original 2008 design, the Zombie Plague was meant to last a lot longer and end at roughly the same time the Plague Cure questlines became available. However, due to the initial reaction to the event and how disruptive it was, it was ended significantly earlier than originally intended during pre-patch in 2008. This truncated duration is still reflected in our data and our intent for Wrath Classic was to adjust it to have it last for a full week. This was unfortunately overlooked and was another mistake.

Different Realms are having events start and end at different times – Due to the nature of these events being on rigid timers and being very specifically tied to one another, various realms are now on different timers and stages due to some of the issues we’ve had. Additionally, we’ve spun up a brand new realm in Eranikus-US, which started the Zombie Plague Stage 3 and the Scourge Invasion event about a full day after the rest of the US realms. If we were to open any additional new realms, they would also have this issue. We believe that most realms are on the same general stage at the time I am making this post, but if we allow events to play out without intervention, the subsequent plague cure and city attack/RP events will start and end at wildly different times, depending on the realm/region.

Kalimdor Invasions not functioning – There was a bug in data that was causing the events needed to make these invasions function to not fire on Kalimdor maps. We attempted a fix for this on Saturday, which led to some instability on some realms, so we quickly reverted that fix. We’ve got a new fix on deck that we believe will resolve the issue without the instability, so we will be pushing that fix starting tomorrow 9/13 with normal regional downtimes.

The next steps

As a result of the issues above, we’ve essentially rebuilt the Scourge Invasion, Plague Cure, and Last Chapter/City Attack events to work in a more modern fashion and operate based on game events that we can start and stop independent of one another. The way these events were built in 2008 causes them to be somewhat error-prone, particularly in situations we find ourselves in now where we have to do things such as opening brand new realms, or when we have general realm instability. We also had some (largely invisible to players) issues over the weekend where various timers for various events were incorrect which required us to manipulate the events manually, which also potentially further desyncs the timers.

We’ve had similar problems with other legacy events in past WoW Classic content releases such as the AQ40 War Effort events and it’s pretty obvious at this point that these types of older events just don’t quite function right in modern environments. As much as we’d like to make them play out exactly as they were, we’ll be examining many such events for improvements for future content releases or potential seasons of the various different flavors of WoW Classic to hopefully avoid some of these headaches in the future.

What should you expect between now and launch?

Following scheduled regional downtime tomorrow Sep 13th, the rebuilt versions of the remaining events will be running on live realms.

This means that:

Scourge invasions will continue to play out right up until September 26th at 3:00 p.m. PDT when Wrath of the Lich King Classic officially launches.

The Plague Cure quest events will be available in Shattrath as soon as realms come up from maintenance. This portion of events will also run right up until Sep 26th at 3:00 p.m. PDT when the expansion launches. With the original data this would have ended after 7 days (on Sep 19th), but we are going to let it run for an extra week, to ensure that more players have an opportunity to participate in the content.

Starting at 12:00 a.m. PDT on Monday September 19th, the Last Chapter begins and cities come under attack from the scourge, and various RP events occur as mentioned earlier in the post. This part of the event will also run right up until 3:00 p.m. PDT on Sep 26th.

Overall, we do want to extend our sincere apologies for the confusion around these events. We believe that we are in a much better place now that we’ve modernized how these events work on the back-end and hope to see the remaining events to play out in a much more predictable fashion from here with no additional surprises.

We appreciate the feedback and your patience as we progress through these and other events. Going forward we’d like to get into the habit of doing these type of after-action reports for certain issues like this so that we can hold ourselves as a dev team accountable to our mistakes and also peel back some of the layers of how the game works, as well as showing the challenges we sometimes face trying when working with this older data. Ultimately we are all human and making mistakes helps us reflect on our process and Learn and Grow to improve.

Thank you!