Season 6

Season 6 of GO Battle League lasted from November, 2020 to March , 2021. It is preceded by Season 5 and succeeded by Season 7. Starting on this GO Battle League Season, all future Seasons run concurrently with in-game Season. This GO Battle League Season ran concurrently with Season of Celebration.

As mentioned in the GO Beyond announcement, the GO Battle League will expand from 10 to 24 ranks, and the top four ranks will have all-new names and corresponding badges, namely Ace, Veteran, Expert and Legend. The expanded ranks will be accompanied by a totally new reward structure, which gives Trainers more opportunities to earn exclusive rewards through ranking up. Rewards are tied to the theme of the Season as well.

Ultra Premier Cup and Master League Classic were introduced in this Season. The latter only allows Pokémon that have not been powered up by Candy XL.

Information of the second half of this Season was announced on January, 2021. It also mentioned Master League will be reworked.

During this Season, Trainers still did not require walking to unlock battle sets.

Formats
Holiday Cup: Only Normal-, Grass-, Electric-, Ice-, Flying-, and Ghost-type Pokémon allowed. 1,500 CP limit.

Love Cup: 1,500 CP limit. Allowed Pokémon:

Charmander, Charmeleon, Charizard, Vileplume, Paras, Parasect, Krabby, Kingler, Voltorb, Electrode, Goldeen, Seaking, Jynx, Magmar, Magikarp, Flareon, Ledyba, Ledian, Ariados, Yanma, Scizor, Slugma, Magcargo, Octillery, Delibird, Porygon2, Magby, Torchic, Combusken, Blaziken, Wurmple, Medicham, Carvanha, Camerupt, Solrock, Corphish, Crawdaunt, Kricketot, Kricketune, Trash Cloak Burmy, Trash Cloak Wormadam, Magmortar, Porygon-Z, Wash Rotom, Tepig, Pignite, Emboar, Pansear, Simisear, Throh, Venipede, Scolipede, Krookodile, Darumaka, Darmanitan, Dwebble, Crustle, Autumn Form Deerling, Spring Form Deerling, Shelmet, Accelgor, Pawniard, Bisharp, Braviary, Heatmor, Fennekin, Braixen, Delphox, Fletchling, Fletchinder, Talonflame, Clefairy, Clefable, Jigglypuff, Wigglytuff, Slowpoke, Slowbro, Exeggcute, Lickitung, Happiny, Chansey, Mr. Mime, Mime Jr., Porygon, Cleffa, Igglybuff, Flaaffy, Hoppip, Slowking, Snubbull, Corsola, Smoochum, Miltank, Blissey, Whismur, Skitty, Milotic, Gorebyss, Luvdisc, Cherubi, Sunny Form Cherrim, Lickilicky, Audino, Alomomola, and Scrafty.

Ranks and Ratings
This Season saw an increase in the ranking system with it going from 10 to 24 ranks. Rating is only shown after reaching rank 20.

There were some differences of requirements in game code before Season 6 started, which can be found in this link.

Rewards
This Season included a unique reward track in certain ranks, meaning all five slots give the same rewards in those tracks. The rewards of the remaining ranks stayed the same as previous Seasons.
 * Rank 5: Mysterious Item
 * Rank 10: 750 (Basic) / 1500 (Premium) Stardust
 * Rank 15: 1 (Basic) / 2 (Premium) Rare Candy
 * Rank 19: Pokémon Encounter

Basic Premium

Stardust

The random items can include:
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Reaching rank 19 awarded:

Reaching Legend rank awarded avatar items and an avatar pose inspired by N from Pokémon Black and White.

Pokémon
Bulbasaur was the first guaranteed encounter. After that, each Starter Pokémon was the first guaranteed encounter of the rank shown below, those from ranks 2 to 14 being encountered only once. Frillish was a guaranteed encounter at rank 20 once it released. Pikachu Libre was the first encounter in Legend rank, one only.

Tier 5 Raid Bosses could be obtained starting at rank 20 during their time in raids.

These Pokémon were released at the start of the second half of the Season:

These Shiny Pokémon were released at the start of the Season: PS Pikachu

End-of-Season rewards

 * (rank 19 or above)

Attack updates
These Attack updates went live on January, 2021:

Attack changes

 * Ember: Base power increased from 6 to 7 in Trainer Battles.
 * Karate Chop: Energy gain increased from 7 to 8 in Trainer Battles.
 * Bubble: Base power reduced from 8 to 7 in Trainer Battles.
 * Razor Leaf: Base power reduced from 11 to 10 in Trainer Battles.
 * Crabhammer: Base power increased from 75 to 85 in Trainer Battles.
 * Sky Attack: Base power reduced from 80 to 75 in Trainer Battles.
 * Rock Slide: Base power reduced from 80 to 75 in Trainer Battles.
 * Shadow Bone: Base power reduced from 80 to 75 in Trainer Battles.

Attack availability
Some Pokémon received new Attacks to their standard Attack pools:

Events

 * GO Battle League was temporarily closed for a while after the global downtime on December, 2020.
 * Suicune was erroneously in the rewards on January, 2021 for few hours. The correct Pokémon was supposed to be Raikou.
 * GO Battle League was temporarily closed twice during Pokémon GO Tour: Kanto on February, 2021.