[WoTB] Blitz Matchmaker

World of Tanks Blitz uses basically the same matchmaking system from the PC version of the game, only slightly optimized for faster performance and 7vs7 battles.

First, it would be good to watch this video for the PC version.

• There are no particular restrictions on vehicle nation, class, tier, etc. Same as on PC.
• MM-ing spread is 2 tiers for most of the vehicle tiers, apart from tiers 1 and 2. Tier 1 can only play with tiers 1 and 2, tier 2 can play with tiers 1, 2, 3. 
• Platooned players are matched based on highest tier in platoon.
• Balance weights for all classes in Blitz are the same, i.e tier 7 mediums, heavies and tank destroyers all have the same balance weights. 
• Premium tanks may have preferential matchmaking, eg A-32 can only play against tier 3-5 vehicles, Pz IV Hydro, KV-220, M4A2E4 - only against tiers 3-6, Panther M10 - against tiers 5-8, KV-5 - against tiers 6-9.

Ideally, matchmaker tries to create full 7vs7 battles, ensuring that top 3 vehicles in both teams are of the same tier, and balance "weights" of both teams are equal.

The longer the wait time in the queue, the softer matchmaker requirements become. The requirements change twice - after 30+ and 60+ seconds in the queue.

After 60+ seconds for one of the waiting players matchmaker would try to create battles with less players on the team where minimal size is 3, i.e. 3vs3 battles. In such battles, at least 2 top vehicles are to be on the same tier, while matchmaking "weight" difference between the team can go up to 10%.

Unfortunately, there are some rare bugs which carried over from the PC version to Blitz, and in Blitz they are reproduced more frequently:

Such battles, where top 2 equal tier requirement is not enforced, could be created after 60+ seconds of wait time for one of the queued players. We will be monitoring the situation and trying to fix this.

After 5 min wait time, player is kicked out of the queue to garage due to timeout.