Set 4 (Mezastar)

The fourth set marked the Pokémon Mezastar debut of the Gigantic Pokémon Eternatus and the High King Pokémon Calyrex, appearing in both its Ice Rider and Shadow Rider forms. Both Pokémon were featured as Grade 6 Superstar Pokémon; Eternatus also had two tags with different artwork and moves. Other Superstar Pokémon included Pokémon X and Y mascots Xerneas and Yveltal, the Renegade Pokémon Giratina, the Bulk Up Pokémon Grimmsnarl, the Stealth Pokémon Dragapult, and the Wolf Pokémon Lycanroc. Grimmsnarl supported the Dynamax mechanic, as did Grade 5 Star Pokémon Tyranitar and Metagross. Lycanroc could use a Z-Move, as could the final evolutions of the Kanto starter Pokémon: Venusaur, Charizard, and Blastoise. Star Pokémon Lucario and Gardevoir also supported the Mega Evolution mechanic. The set also featured the Mythical Pokémon Marshadow, several other Generation VII lines, as well as the final Eeveelution as of eighth generation, Sylveon.

Members of the Mezastar Club could access new features with the launch of this set, including the ability to customize their avatar with Fashion Items (Japanese: きせかえアイテム), use Battle Tickets (Japanese: バトルチケット) to challenge Trainer and Battle opponents again at will, and redeem Present Tickets (Japanese: プレゼントチケット) to unlock special in-game items or limited Fashion Items. Five new Trainers could be challenged during gameplay and defeating them all would unlock their Battle Tickets on the Mezastar Club. The tickets would also become available to members a certain period of time after the set's launch, regardless if they had yet to defeat all five opponents. Mezastar Club members could also receive a Flygon digital Support Pokémon Ticket for the duration of this set.

Battle Tickets displayed the name of a Trainer, the player's highest score against them, the overall rank of that score, and a QR Code for use with the console Multi-Scanner. The tickets also tracked any Fashion Items a player could earn from them. One item, typically clothing matching the opponent's attire, could be unlocked for defeating them once, while challenge items could be unlocked by completing a set of three challenges during battles. These items could be differently-colored versions of the regular clothing, or new items entirely. Players could update the appearance of their avatar through the Mezastar Club, which would subsequently update on any machines after scanning their Memory tag. A limited Battle Ticket that allowed players to challenge Mezastar Navigator Sakura could be accessed through the Mezastar Club between May 7 and September 15, 2021. A Present Ticket that unlocked school-themed Fashion Items could be redeemed through the club for the duration of the set.

Much like the fourth Pokémon Ga-Olé set, the Trade Chance! (Japanese: こうかんチャンス！) feature was added with the launch of this set, which had a chance to trigger during the Get Time! or Last!! Get Time! phases. An icon would appear on the "throw a ball" option if the player could activate Trade Chance! If selected, an older version of one of the player avatars would appear after a Pokémon had been caught and present the player with a random Pokémon to trade. The player could select either the offered Pokémon or the one captured originally using the "L" and "R" buttons.

Three new Partner Pokémon were available to players with Memory tags from this set: Gastly, Beldum, and Impidimp. More Support Pokémon could also be added to the player's starting roster with the release of physical Support Pokémon Tickets in Shogakukan publications.

Partner Pokémon

Gastly Lick → Haunter Shadow Punch → Gengar Hex

Beldum Tackle → Metang Metal Claw → Metagross Meteor Mash

Impidimp Bite → Morgrem Sucker Punch → Grimmsnarl Spirit Break

Support Pokémon Tickets

Available through the Mezastar Club from April 22, 2021 Valid until September 15, 2021 Flygon Earthquake	Available in the June 2021 issue of CoroCoro Ichiban!, released on April 21, 2021* Valid until September 15, 2021 Corviknight Brave Bird
Available in issue 73 of Pokémon Fan, released on April 28, 2021 Valid until September 15, 2021 Mimikyu Shadow Claw

Trainer and Battle opponents

Video Creator Taichi どうがクリエイター タイチ Difficulty: ★☆☆☆☆ Lucario Flash Cannon Rowlet Leafage Mareanie Venoshock Galarian Meowth Metal Claw

Police Officer Mamoru おまわりさん マモル Difficulty: ★★☆☆☆ Decidueye Grassy Glide Eevee Swift Bewear Strength Boltund Spark

Band Girl Rise バンドガール リセ Difficulty: ★★☆☆☆ Gengar Sludge Wave Pangoro Brick Break Galarian Weezing Sludge Sandaconda Dig

Magician Yōji マジシャン ヨウジ Difficulty: ★★★☆☆ Grimmsnarl Spirit Break Alolan Muk Poison Jab Corviknight Drill Peck Magnezone Zap Cannon

Star Trainer Hitomi スタートレーナー ヒトミ Difficulty: ★★★★☆ Xerneas Moonblast Lucario Aura Sphere Flygon Dragon Claw Mimikyu Shadow Claw

Mezastar Navigator Sakura メザスタナビゲーター サクラ Difficulty: ★★★★☆ Pikachu Thunderbolt Leafeon Leaf Blade Rayquaza Draco Meteor Mewtwo Psystrike