World of Tanks is a team-based massively multiplayer online action game dedicated to armoured warfare in the middle of the 20th century. The core of its gameplay consists of two teams made of 15 players, fighting on a battlefield against each other.
In order to ensure that the “random battles” (the main game mode) keep the interest of our players, the following three conditions need to be respected in every battle:
- Equality among the vehicles present on the battlefield within the two teams
- Variety in the type of vehicles present on the battlefield
- Unpredictability of the course and outcome of the battle
This task is being performed by a special module/system that is located on the server side of the game, the so-called “Match Maker”. This selects the tanks for both teams, makes sure that the teams are even and that each battle can start.
When the “Match Maker” first appeared in the Closed Beta (there was none during the Alpha stage), there were only two types of battle levels:
- Sandbox with tanks from the 1st and 2nd tiers
- Common battles comprising all the other tiers (3-10)
Since then our “MM” has evolved and a whole new sophisticated table composed of 12 types of battles was born (battle tiers).
The first 10 battle types roughly correspond to the tiers of the vehicles and their placement in the various Tech Trees. For example, a Tier IV heavy tank can only get into battles with other Tier IV and Tier V tanks.
Beyond that every tank has a so-called “balance weight”, which is a hidden numerical parameter that determines the combat effectiveness of each vehicle. It is directly linked to the type of the vehicle, its tier and role (we have chosen) in the battle.
- Any vehicle can get into fights that correspond to its tiers (see table), with the exception of platoons
- 所有车辆进入对应的分房等级（见上附图表 点击可放大），除非组队
- The place that a vehicle receives in a team is assigned according to the “balance weight”
- Vehicles are selected according to the battle statistics within the last half hour
- The total “balance weight” of the opposed teams must not differ by more than 10%, except in special cases
- The total “balance weight” of the SPGs in the opposed teams must not differ by more than 20% – a team can have only one more SPG and the total number of SPGs cannot be more than 5
The more times a specific vehicle is waiting to join a battle, the higher its priority. If you wait more than 1 minute, the “MM” will assign top priority and you will be sent into battle at the first open slot.
If, during the balancing process, both teams do not meet the requirements mentioned above, they will be disbanded and the whole process for team composition starts again.
The settings that are not taken into the account are:
- The nation of the vehicle
- The researched and available modules (gun, turret, engine, etc …)
- Mounted accessories and/or equipment
- Crew skill level
- Player skill
The “MM” works with queues of vehicles. Each tier and type of battle has its own queue. There is 36 different queues in total (12 levels of tiers, multiplied by 3 different battle modes).
The battle statistics are collected separately for each queue. In addition to this, the statistics for SPGs are also collected separately. We use this statistical data to decide on the balanced weight of every vehicle.
To understand it better, let’s take a concrete example: we have chosen an American heavy tank – T14 – characterised by the fact that it can get into battles of 5th and 6th tiers. To keep the example simple, “Encounter” and “Assault” have been deselected.
为了更好地理解它，让我们的一个具体的例子：我们已经选择了一个美国的重型坦克- T14 -，它的分房等级是5-6。为了尽可能简单，“夺旗”和“攻防”模式已被取消
So now our tank is in the queue and, as you can see, its priority to join the battle is low. However the “MM” is scanning the entire queue during the selection process, and thus if there is an empty spot that more or less corresponds to the balance weight of the T14, it will immediately be sent into battle. Conversely, it might also need to wait. Every time a pair of teams is sent into battle, the team composition process starts over and over again.
SPGs are always the first vehicles to join a team. After that the “MM” will start looking for the tanks to fill the remaining empty spots. Vehicles with high balance weight (top vehicles) are added right after the SPGs.
When adding a platoon the “MM” will try to make sure that the balance weight of the tanks in the platoon equals the balance weight of the remaining free slots (where tanks with big balance weight still have top priority).
As mentioned above, the “MM” will make sure that the difference between the “balance weights” of both teams is not more than 10%.
The balance weight of the available slots can also be adjusted to the tanks that are currently waiting in the queues.
Once a pair of teams is created, the teams are checked for all the conditions mentioned in the “MM” criteria again, and are then sent to the battlefield. If the required criteria are not met, the teams will be disbanded and the match making process starts again (where this process is not visible to players and happens entirely behind the scenes).
It may also happen that the “MM” is not able to complete the team creation process (for example: there are too many vehicles of the same type in one team). In such a case, the whole queue is frozen until tanks with other settings join it, or the already pre-selected tanks move into other queues.
On the picture you can see that T14 ended up in two different queues:
- A Tier V queue that is already completed
- A Tier VI queue that is still in the completion process (too many KV-1S)
At this moment, the tank disappears from both queues. This means that the Tier VI queue has now an empty slot.
Please also note the following factors:
- The longer your waiting time, the higher priority there is from the “MM” to send you into battle
- If the waiting time goes beyond an acceptable limit (1 minute), the selection criteria will not be fully respected (such as: not enough vehicles, or only the same types of vehicles present)
- If the waiting time is more than 2 minutes, the “MM” has the ability to create a partially completed team (with less than 15 players on each side)
- If the waiting time is more than 5 minutes, you will receive a message inviting yor to go back to the garage and select a different tank
Some of the situations described above may appear during the launch of new servers, new regions or when the number of online players is low (such as during the middle of the night).
We are constantly working on the improvement of the game “MM” and some additional changes were added in Patch 0.8.5. Our goal remains to provide you with best game experience.
I hope that you have enjoyed reading this article and will leave the thread open to gather more questions that we may use to update this article in the future.
Please note that all non-constructive questions and comments will be deleted.
P.S The localisation of this article into other languages is currently in progress.