[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. 

Zig-Zag

The story of German spies in Britain is without doubt a story of woe and failure.  Laughably unprepared agents were being inserted into Britain and most were captured within days if not sooner.  However there is one exception.

In the spring of 1939 Eddie Chapman was facing 40 counts of burglary.  He loved explosives, and used his knowledge to blow numerous safes throughout London.  He then shifted his attentions to Scotland where his luck ran out and he was arrested.  However using his remarkable charm and charisma he managed to get bail.  Of course it will come as no surprise that he immediately jumped his bail.  Grabbing his fiancée they took a flight to the Channel Islands, and booked themselves on a boat to South America.

The boat was due to leave the following day, so Chapman and his fiancée headed out for lunch.  As they ate Chapman spotted two policemen closing.  He simply rose, kissed his date goodbye and dived head first out of the closed window.  A chase down the beach then followed, but Chapman managed to give the police the slip.

Then he made a decision that would change the rest of his life, he carried out a rushed and ill planned burglary.  When he was caught he was sentenced to be imprisoned in the Jersey Islands for 2 years, then to be returned to mainland for the charges there.  However while in prison the Germans invaded.  Playing on a chance Chapman immediately volunteered to join the Germans.

After months Chapman was selected for training, and several more months of instruction followed.  But in December 1942 Chapman was given his first mission.  Armed with a pistol, some detonators, a wireless and a suicide pill Chapman was parachuted into Britain.  His target was to blow up the Mosquito factory at Hatfield.

Chapman was also given £990 of cash, but the piles of bank notes were held together with bands that said "Reich's bank, Berlin".  Even the pilot of the German plane later confessed that he thought Chapman had no chance of survival.

First he needed some explosives. He used his earlier knowledge and raided a quarry near Sevenoaks coming away with a substitutional pile of explosives.

All was set.  On January the 29th 1943 Chapman found himself lurking in the darkness made all the more profound by the blackout, next to the perimeter fence of the Hatfield factory.  He quickly scaled the fence and moved in.  He found the powerhouse of the building and planted his charges before withdrawing not having seen a single soul.

At midnight a huge explosion rocked the factory, blasting holes in the buildings walls, and smashing several transformers, throwing two to the ground.  Following Chapman's triumphant radio message to the Germans they sent over a plane to photograph the damage.  Remarkably the Reconnaissance plane had a very quiet flight, and returned with pictures showing the wide devastation.  Equally stories appeared in the Daily Express which confirmed the attack.

The Damage at Hatfield

Chapman was congratulated, and ordered to return to Germany via Portugal.  Chapman signed on as a crewman on a merchant ship and upon reaching Portugal he went ashore on leave.  He immediately returned to the German Embassy. He then used his initiative and asked the Germans at the embassy for an explosive shaped to look like a lump of coal.  He smuggled that back on board and stowed it in the coal bunker.  When sailing back to Britain the explosive would be loaded into the furnaces and detonate hopefully sinking the ship.

SS City of Lancaster, Chapman's ship to Portugal

Chapman was then returned to Germany, and sent to Norway where he spent considerable time within the German intelligence community.  For his services he was awarded the Iron Cross.

In 1944 Germany needed every asset it could get, so Chapman was dispatched back to London.  His job was to report on the fall of the V1's being launched at London.  Chapman remained at large for the rest of the war sending back precise targeting information for the V1 launches.  This enabled the Germans who had been overshooting their targets to lower the range and effectively bombard the capital.

Or at least that's what the German intelligence service thought had happened.

Back in December 1942 as soon as he had landed Chapman gone to the nearest house he could find and telephoned the police and handed himself in.  And he had then volunteered to be a double agent, codenamed "Zigzag".  The Hatfield bombing had been achieved by the special effects department from the Old Vic theatre.  The newspaper story in the Daily Express was a plant.  Originally MI5 had approached The Times to run the planted story, however the editor had refused stating:
"Nothing untrue had ever been published and he wasn't about to start now!"

Faked damage at Hatfield

The merchant ship in Portugal hadn't been sunk, as Chapman had handed the explosive to the ships captain and explained what was going on. He asked him to hand it into the authorities when he returned to England, which also allowed the British to obtain a sample of the latest German explosives.

While at the Norwegian safe house Chapman had covertly photographed all the visitors, including several spies, and then through a female fiancée in the Norwegian underground smuggled that information to the British.

On his return to London the V1's had been hitting perfectly, but due to Chapman stating they were overshooting the range was dropped and the bombardment caused less damage than it should have done.

Chapman, shortly before his death in 1997, being interviewed by the BBC.

After the war Chapman tried to get his story out, but failed as the Government hit it with a D-notice.  So he went abroad to publish and make it into a film. He married his first fiancée, the one he'd last seen in the Channel Islands, and lived in Spain until he died in 1997.