World of Warships

Development blog


0.9.5, More details on changes of Unique Upgrades


Following the reveal of the Unique Upgrades balance changes, we noticed quite a lot of questions and concerns about the reasoning behind the buffs and nerfs announced. There was some confusion around various of the changes and some of you found it hard to justify them, as they seemingly contradicted a pre-existing perception of particular ships and upgrades.

We appreciate your involvement in this interesting topic, and we'd like to share more details and insight about how we approached UU balancing. Hopefully it will give you more context for the planned changes. The information below is up-to-date and current. Depending on further tests and changes, our approach may still be altered. 


First of all, let's define what a Unique Upgrade (UU) should and should not do by as per the current design:

  • It should create additional variety in how players can build their ship by providing an alternative option to the existing upgrades.
  • It should either emphasize a particular playstyle on the ship or, alternatively, suggest a new way to play it.
  • It should not overshadow other upgrades in the same slot, making the ship overpowered, and the upgrade itself mandatory for optimal performance.
  • It should not be the way used to buff or nerf the a ship itself, as for this purpose the ship itself should be adjusted, not its UU.

From this point of view, when balancing the upgrades we decided to concentrate on the following stats, looking at our active players who own the UU for the respective ship:

  • Popularity: what's the share of battles on the ship that were played with the UU? It's a pretty simple metric, e.g. "X Hindenburg's UU popularity is 54.5%" means that 54.5% of battles were played with the UU equipped (that's the real numbers, by the way, as are all the numbers in this article). 
  • Winrate difference between the players using and not using UU, and ships having it equipped or not: how (and how much) does the upgrade influence player winrate on the ship? Besides pure ship winrate comparisons, we should also consider how people play with UU and how well they play in general.
    • In most cases, fitting a UU with a purpose may "buff" the results, because that particular playstyle fits these particular players (i.e. some people are very effective playing X Minotaur with radar or X Des Moines with spotter plane, which does not necessarily mean that these configurations are optimal or even overpowered).
      • Player winrate is more important than the winrate of the ship. An experienced player can play any ship effectively, but the ship's winrate is calculated based on all players in the sample. That's why the difference in winrate may be below zero.

With that in mind, we calculate WR difference for UU as:

  1. (WR difference between UU equipped ships and those without it) minus (WR difference between players using UU and not using UU but owning it) gives us our actual UU WR difference
  2. Because of the nuances above, as well as the facts that player account WR has more impact on battle performance than the WR on a particular ship, we consider the results of up to +2% acceptable. For example:
    1. X Des Moines: ships WR difference (6,7%) - Players WR difference (3,9%) = +2,8% difference. Above the acceptable 2%, which means the upgrade is too strong.
    2. X Shimakaze: ships WR difference (-0,1%) - Players WR difference (-0.1%) = 0% difference. Acceptable.
    3. X Gearing: ships WR difference (1,5%) - Players WR difference (0,3%) = +1,2% difference. Fully acceptable. 

We've set the following targets:

  • UU's popularity should not be significantly above 65% - if it is, that's a sign that the UU is becoming a no-brainer instead of being an alternative. 
  • UU's popularity should not be significantly lower than 40% - if it is, that's a sign that the UU doesn't offer an interesting enough alternative to the existing upgrades.
  • The UU should not make the relative WR worse (in this case it becomes a downgrade, not a sidegrade).
  • The target WR limit is +2%, as was explained above.
  • Each UU case should be reviewed individually before the suggestion of a final version.

These values are not strict and serve as indicators - the decision to more precisely check the peformance of UU is based on them. Besides these values we also consider feedback and expert review. 

From this point of view, we could look at several examples in depth:

X Großer Kurfürst (56,88% popularity, +2,0 WR).

Changes to UU
  • Bonus to main battery reload time was reduced from 15 to 10%;
  • Penalty to main turrets traverse speed was removed.

Some of you were upset by the nerf, and we appreciate these feelings. But unfortunately the UU for this ship was a bit too effective and also pretty popular. The 5% nerf to main battery reload time bonus (from 15 to 10) may seem scary on paper, but comparing to the most popular "Main Battery mod.3" the UU actually provides:

  • Only -2% main battery reload speed
  • -8% worse main gun range
  • +15% secondary armament reload speed
  • +13% turret traverse speed

For the safer playstyles, secondary armament DPM and turret traverse speed do not matter that much, but for aggressive and risky pushes the bonus is very considerable - and the UU in this case suggests exactly that, with a manageable trade-off. 

X République  (22,53% popularity, +0,2 WR).

Changes to UU
  • Penalty to main turrets traverse speed was removed.

There were some questions about this UU as a whole and claims that nerfing the range in favor of main battery DPM on this ship makes no sense, and that the turret traverse was not a problem in the first place. It's a good case to explain the "alternative playstyle" approach. X République is a very potent medium and long range battleship, but her UU suggests a riskier playstyle. If you're going to play it safe, sure, it was, and still is better to go with the regular upgrades of your choice. But if you find yourself in close quarter combat more often than not, which is a valid way to play too, this UU provides you the buffs specifically for that and the turret traverse starts to matter more and more. As we can see from the popularity, it's relatively small, but the performance is already pretty good. Hence, we're trying to make the suggested playstyle more pronounced instead of a straight flat buff. 

X Montana (66,85% popularity, +1,1 WR)

Changes to UU
  • Bonus which reduces fire extinguishing time was reduced from 15 to 10%;
  • Bonus which reduces flooding recovery time was reduced from 30 to 10%.

In the case of X Montana, it is important to distinguish the ship from her UU. As we've said previously describing the concept, UU should not be too powerful and should not overshadow other upgrades in the slot. Thus the changes are directed at lowering the popularity of UU and not on the ship.

X Khabarovsk (62,05% popularity, +2,5 WR)

Changes to UU
  • The penalty which reduced main turret traverse speed was removed;
  • Bonus to the main battery firing range was increased from 8 to 10%;
  • The 20% penalty to the action time of consumables was added

New UU lowers the WR difference and offers a playstyle when survivability is provided not by the number of consumables, but by fighting at long ranges.

X Shimakaze (23,56% popularity, +0 WR)

Changes to UU
  • The penalty which reduced torpedo tubes traverse speed was reduced from 80 to 70%.

Despite having an acceptable WR difference, the UU has rather low popularity. This is related to the fact that this UU is mostly effective with 20-km torpedoes and UU fits its purpose for those, who like long-ranged torpedo attacks.

X Worcester (24,01% popularity, -2,5 WR)

Changes to UU
  • The upgrade was moved from Slot 5 to Slot 6;
  • All bonuses to consumables action time were removed;
  • Bonus which reduces the priority AA sector reload time by 20% was added;
  • Bonus which reduces the reload time of ship's consumables by 20% was added;
  • Bonus which inreases the number of all consumables by 1 was added.

UU had rather weak positive effects and was in slot 5, competing with concealment and Radar duration upgrades. This caused low popularity and we've decided to keep the concept for this UU (strengthening X Worcester as a support ship), but empower it a bit and make it an alternative to firepower upgrades instead of concealment.

X Yueyang (26,53% popularity, -1,1 WR)

Changes to UU
  • Bonus which reduces main battery reload time was increased from 10 to 15%;
  • Penalty to the action time of consumables was removed;
  • Bonus which increases the action time of the "Surveillance Radar" consumable by 20% was added;
  • Bonus which increases the smoke screen dispersion time by 20% was added;
  • Bonus which reduced torpedo tubes reload time was removed.

UU was unpopular due to the large number of negative effects: it lowered her competitiveness in comparison to other upgrades and the ship's WR. The updated UU offers more aggressive gameplay with an emphasis on consumables and main caliber instead of concealment upgrade, which is suited for more cautious gameplay.

Since our last announcement we've changed two UUs:

X Des Moines (65,76% popularity, +2,8 WR)

UU had excessive efficiency and high popularity. Initially, we thought that this playstyle's efficiency would be lowered by the announced changes, however, testing showed that it won't. That's why we've decided to implement different changes:

  • Reduced the bonus to engine power. Now with the unique upgrade and the "Propulsion Modification 1" upgrade, it'll take the cruiser 21% more time to reach maximum forward speed, and it'll take three times more time to reach maximum backward speed. The ship will still be gaining speed faster with these two upgrades compared to having just one of them. At the same time, the time it takes the ship to reach 1/2 and 3/4 of her speed remains almost the same.
  • Removed a penalty on the action time of Surveillance Radar. This penalty didn’t affect the use and effectiveness of the upgrade.

Players will now choose between this unique upgrade and an upgrade that increases firepower.

X Henri IV (62,01% popularity, 0,7 WR)

The upgrade had high popularity, which was the target of the changes. However, the WR is acceptable. Besides that, we've considered your feedback and decided not to implement changes to the UU at the current time and see what the effect of the changes for X Henri IV in Update 0.9.5 will be. For now, UU will keep its parameters:

  • -12% main caliber guns reload time
  • +8% main caliber guns maximum firing range
  • +10% detectabilty.

We didn't change UU of several ships because their metrics are fine:

  • X Gearing (63,59% popularity, +1,2 WR)
  • X Conqueror (64,29% popularity, +0,3 WR)
  • X Hindenburg (54,5% popularity, +1,1 WR)

We see the UUs of X Yamato, X Moskva, X Zaō, X Minotaur, X Z-52, and X Grozovoi as candidates for future changes and will share info about them, UUs for CVs, and for ships which don't yet have them, in the near future.

Hopefully, we were able to give you more context to understand the changes to Unique Upgrades.  Of course we will keep looking at their performance and how the changes will influence it in the following updates. If something does not work, we can always make further tweaks to reach the optimal performance, while keeping each unique upgrade as an interesting and valid choice.

Good luck and fair seas!