[Data Analysis] The Most Difficult Encounter in WoW history


Guild Master
Data Analysis – The Most Difficult Encounter in the history of World of Warcraft.
This data analysis is aimed at finding which boss was statistically the hardest boss to kill in the history of World of Warcraft. Due to data not being accurately collected until 2008, it is very difficult to come to a concrete answer. However, with the data available, I am able to come to several conclusion and make the argument that one boss was in fact, the most difficult encounter to defeat in the history of World of Warcraft.
This is not a subjective analysis. Many may try to point out factors such as mechanics or relative difficulty from their experience. This is an objective analysis using data available. It may or may not be 100% accurate due to not having all the data available. But it is simply a statistical analysis.
The majority of the statistics were obtain via WoWprogress.com, the premiere website for tracking boss kills. The statistics in question are as follows:
· Subscription numbers
· Number of guilds that were raiding at the time.
· Number of guilds defeated the encounter when it was active.
· Availability of the encounter while it was active.
Because of the nature of the data, I will also be introducing several factors to accompany my analysis. This should suffice the majority of concerns about simply looking at raw data.
Factors to consider –
· Encounter tuning (Nerfs or lack thereof). Minor hotfix nerfs will not be considered.
· Resources available for players at the time (Websites, kill videos, guides, split runs, lockouts)
· Timing of the Raid (mid/late-expac)/Accessibility
· Encounter Gating
· Human Factor (Relative competition, strategies)
Get sub numbers during each period.
Get dates for release of the boss and when it was first downed and when it was unavailable.
The number of guilds raiding during this time has been tracked by WoW progress since 2009. If a guild killed a boss during the tier, the website tracked progression kills via percentages which can still be seen on the website.
An “active” kill for this research is a kill that was obtained before the release of the next content tier/pre-patch.
I was very interested in trying to find overall data for Vanilla encounters. I have heard previously that C’Thun was mathematically unkillable for several weeks. I have also heard that only 21 guilds defeated Kel’Thuzad during Naxx-40. However, I am unable to find any data on these. Therefore, I am only able to compare encounters to which there is data which would be Sunwell Plateau and onward.
Throughout my research, it was very quickly revealed that there would be 3 bosses that would be in consideration as being the hardest bosses statistically to defeat: Kil’Jaedan, Lich King (25m Heroic), and Mythic Blackhand.
Kil’Jaeden was the final encounter in the Sunwell Plateau raid during the Burning Crusade expansion.
Active subscriptions while this encounter was active: 10 million
Number of guilds that were killing bosses during this tier/raid: Unknown
Number of guilds defeating the encounter while active: 377
Release Date: March 25, 2008
First Kill: May 25, 2008 (62 days after release)
Last Date for active kill – October 15, 2008.
Availability for active kill: 204 days
The Case For: KJ is a boss not many raiders had the opportunity to see, let alone get close at killing it. Sunwell Plateau in general was not tuned properly and Blizzard has come out and said they did not bother fixing it because WotLK was on the horizon. The numbers do not lie, only 377 guilds were able to defeat this encounter with an average subscriber base of 10 million+, there were plenty of people available to try and kill this boss. Very few even dared. It took over 2 months for SK Gaming to finally defeat Kil’Jaeden for the World First kill.
The Case Against: While raiding was not as fine-tuned as it would become at the time, it was available for X months. Players seemed to have ample time to get more kills in, but it is clear that raiding wasn’t a top-priority amongst the majority of the population. It wasn’t until Wrath that raiding became the premiere content that the playerbase embraced. Competition wasn’t as relevant as it would become later on. The number of 377 guilds killing KJ can also be explained by the fact that Sunwell was a “gated” raid due to attunements. Therefore not many people would even try to get until the instance, let alone go after KJ. It’s hard to say that a boss was hard if players can’t even try it out without beating the other raids before it. However, they did have 204 days to do it. The raiding population cannot be conclusively ascertained at the moment. Therefore comparative numbers cannot be obtained and a full disclosure of the case against Kil’Jaedan is not feasible.
Lich King (25-Man Heroic)
Active subscriptions while this encounter was active: 11 million
Number of guilds that were killing bosses during this tier/raid: 59356 (25-man ICC), 84136 (10-man ICC)
Number of guilds defeating the encounter while active: 1101
Release Date: February 2, 2010 (Date Lich King encounter was opened)
First Kill: March 26, 2010 (52 days after release)
Last Date for “counted” kill – November 23, 2010.
Availability for active kill: 294 Days
The Case For: Blizzard actually came out and said that more people were raiding during Wrath than at any period in the game’s history (Source Patch 5.4 Roundtable, quoted by Tom Chilton). The fact that this boss had more people with the opportunity to face this encounter make this one of the toughest encounters ever simply put by how many people actually got the boss down. Relative competition and the player pool cannot be ignored. So very many people raided ICC, only 1101 got it down. Unlike previous raids, the Lich King would not become available until (DATE) due to gating. The resources available at the time were out there, but not as pronounced as it would become towards the end of Cata/MoP-era. Players were delegated to using Elitist Jerks and other forums for strategies and outlined boss kill videos were mainly provided by TankSpot. Icecrown Citadel was nerfed 5% overall every week until it reach 30%. It was also an end-expansion raid that was out for nearly 300 days. Players had lots of time and help from Blizzard to kill this boss but many were still unsuccessful. It took 52 days before Paragon could shatter the soul of Arthas. Guilds were also impeded in their efforts by limited attempts per week on the boss. Something no other raid had ever introduced.
The Case Against: Some human factors come into play in the case again Arthas. The emergence of 10-man heroic raiding saw players not even attempting 25-man raids. However, because ICC had 4 separate lockouts (10N, 10H, 25N, 25H), players were able to gear up quite significantly in preparation for the final battle with the Lich King. Other than that, I cannot find many good reasons why this fight was not the most difficult fight to kill. There’s a very strong case for The Lich King, not much against it. Players had plenty of time and ample resources to defeat the encounter. Including a 30% nerf.

Mythic Blackhand

Active subscriptions while this encounter was active: 7.1 million (End of Q1 2015)
Number of guilds that were killing bosses during this tier/raid: Highmaul – 41996. Blackrock Foundry - 32544
Number of guilds defeating the encounter while active: 717
Release Date: February 10, 2015.
First Kill: February 20, 2015 (10 Days after release)
Last date for “active” kill: June 23, 2015.
Availability for active kill: 133 Days
The Case For: It is hard to deny that Warlord Blackhand was the hardest encounter to beat. One of the contributing factors is the sheer amount of guilds raiding at the time, the total number of active kills, and the very short availability of the encounter. Also, it wasn’t very hard to find strategies to defeat this encounter. Video guides, kill videos of other guild’s kills, and the size of the forum community providing insight was at an all-time high. The difficulty of Mythic Blackhand was so great; it can be argued that it was actually the albatross that has sent hardcore raiding into a steeper decline. This encounter broke many guilds, and for good reason. It was fucking hard. Players had ample resources to get this guy down and they couldn’t. Split-runs to gear out mains became the norm. Garrisons offered Mythic gear to any player that could kill the heroic difficulty of the raid. Players were given every chance and tools in the world (of Warcraft) to get him and only 717 did. Addons like Weakauras make certain mechanics trivial these days.
TLDR: A lot of people tried to kill this boss, very few did, and you had a very short window to get the kill.
The Case Against: It’s difficult to truly understand how difficult this boss was against KJ and Arthas because it was a mid-expansion boss. The very short window the boss was open does make it more difficult, but it also makes it more difficult to compare it to the previous examples. However, Method was able to take down Blackhand within 10 days of Mythic raiding opening it. While they may have had more resources and the overall player skillcap has been raised, it’s over a month faster than KJ or LK.
This was not an easy analysis by any means. With this information, you could make the case that any of these three bosses would be most difficult. However as an analyst by trade, I must come up with a recommendation/conclusion.


New Member
C'thun was mathmatically like, 99.999999% impossible before nerf. Available gear was not good enough, the adds both spawned faster than they could realistically be killed while still having to dps the actual boss, and the raid wide damage they did was too much for healing to keep up with, especially given where mana regen was back then. Only Nihilum killed it pre nerf, and that was the night before nerf, with a fully flasked 40 man raid which was kinda unheard of, in literally the best obtainable gear.
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