Super Mushroom vs. Super Star

Super Mushroom (Super size) vs. Super Star (Invincibility) was a Splatfest event in Splatoon 2 held to celebrate the 35th anniversary of the Super Mario Bros. series. It was announced during the Super Mario Bros. 35th Anniversary Direct on 2020-09-03 and was announced in-game on 2020-12-28 at July 27, 2024. The results were given on 2021-01-17.

Notably, this was the final Splatfest in Splatoon 2.

Details
On the 21st of July 2020, the 3rd anniversary of Splatoon 2's release, along with the announcement of the Mayo vs. Ketchup rematch, the Japanese Splatoon Twitter announced that three additional Splatfests were planned to be held before the end of the year.

The Splatfest theme was about two power-ups from the Super Mario Bros. series: the Super Mushroom, which grants super size, and the Super Star, which grants invincibility.

The full name of each choice was "SUPER MUSHROOM" and "SUPER STAR". The team name portion of Splatfest titles was "Super Mushroom" and "Super Star".

Merchandise
Splatfest T-shirts based on the artwork for the event were made available to purchase at the My Nintendo Store soon after the announcement. They are also available on Nintendo's online stores for South Korea and Hong Kong. Additionally, Splatfest keychains can be bought for 100 Platinum Points in North America, Europe, and Japan.

Super Mario Bros. 35th Anniversary medals
To celebrate the Super Mario Bros. 35th Anniversary, special medals were available for participants in North America, Europe, Japan, and Oceania.

Medals were awarded to top 100 players of each team in Japan and Europe, the top 35 players of each team in North America and the top 10 players of each team in Oceania. In Japan, additional 100 random players received the medals as well.

On 2020-12-09, Nintendo of Japan revealed further information about the collectible medals within Japan. On 2020-12-21, Nintendo of America revealed the Splatoon 2 Online Challenge with further details on rules, sign-up and legitability. On 2021-01-12 Nintendo of Europe Twitter mentioned details about the medals within Europe and on 2021-01-13 Nintendo AU NZ mentioned details about the medals within Oceania.

Super Mushroom vs. Super Star featured four Shifty Station layouts that rotate each rotation, with dynamic gimmicks: Cannon Fire Pearl, The Bunker Games, The Bouncey Twins and The Chronicles of Rolonium.

Continuing from Trick vs. Treat (2020), the increased 100× Battle rates that were originally advertised for Chaos vs. Order were still in effect for this Splatfest.

English
Announcement

Introduction

Results

Results if Super Star were to win

Dutch
Announcement

Introduction

Results

Results if Super Star were to win

French (France)
Announcement

Introduction

Results

Results if Super Star were to win

French (Canada)
Announcement

Introduction

Results

Results if Super Star were to win

German
Announcement

Introduction

Results

Results if Super Star were to win

Italian
Announcement

Introduction

Results

Results if Super Star were to win

Japanese
Announcement

Introduction

Results

Results if Super Star were to win

Russian
Announcement

Introduction

Results

Results if Super Star were to win

Spanish (Spain)
Announcement

Introduction

Results

Results if Super Star were to win

Spanish (Latin America)
Announcement

Introduction

Results

Results if Super Star were to win

Trivia

 * This is the first Splatfest with an original theme since Chaos vs. Order - the event that was officially dubbed as the final one. This was referenced by Marina in the announcement dialogue.
 * Marina's confusion at Chaos vs. Order not being the final Splatfest suggests that the previous three rematch Splatfests are considered non-canonical. This is further backed up with how Chaos vs. Order was described as the previous Splatfest in the Japanese dialog, despite the three Splatfests in between.
 * Each Shifty Station available in this Splatfest has some sort of mechanic equivalent to Mario mechanics. Ink Cannons are similar to cannons on airship courses, containment chambers are similar to one-time bonus rooms, Bounce Pads are similar to trampolines, and Rolonium is similar to Koopa Troopa shells that Mario can kick.
 * The ink colors for this Splatfest are absent from being chosen in Private Battles. This trait is shared with Raph vs. Donnie and Hello Kitty vs. My Melody.