Big Run

"I’m not going to sugarcoat it-there are Salmonids everywhere. Just stay focused on the task at hand, and you’ll get through. I hope you had your coffee…"

- Mr. Grizz right when a wave begins.

Big Run is a special event mode in Splatoon 3. The mode was first announced to occur in the Splatoon 3 Nintendo Direct. Big Runs are limited-time events in which Salmonids invade the stages used by Inklings and Octolings for Turf War and Anarchy Battles, allowing players to partake in Salmon Run Next Wave on those stages.

Description
Big Run shifts follow the same pattern as in regular Salmon Run. Four players team up to battle oncoming Salmonids over the course of three waves, splatting Boss Salmonids to acquire Golden Eggs and deposit them in the egg basket. In addition to appearing from the water of the flooded sections of the battle stage, Salmonids can now also spawn from large Gushers that burst open at the start of each wave. After the third wave, a King Salmonid may appear during an Xtrawave. The same rank system is used, with freelance and friend teams both available. The same bonuses are granted, but the number of capsules in the bonus meter is increased during Big Run. Additionally, a 1.2x multiplier is applied to Catalog Points earned from shifts during the event.

Three different tide levels can occur on each wave. High tide and low tide take place in the same location on the map, with high tide making certain areas inaccessible, while normal tide moves players to a different location with its own egg basket. This differs from normal Salmon Run, where high tide and normal tide are played in the same location and low tide has a different location. Big Run also features the Known Occurrences of Rush, Fog, The Griller, and The Mothership (Cohock Charge, Goldie Seeking, Mudmouth Eruptions, and Giant Tornado are not available). The possibility of Rush and The Griller is still constrained by the wave's tide level, but each can appear in both playable locations on the map, unlike in normal Salmon Run.

During the event period, Big Run replaces access to regular Salmon Run shifts through the Grizzco lobby, similar to how Splatfest Battles restrict access to non-Splatfest Turf War battles and Anarchy Battles. Normal battles are still available, but the current Big Run stage is unavailable in any rotation until Big Run is over.

At the announcement and starting times of Big Run, a warning and recruitment message is delivered by Deep Cut during the Anarchy Splatcast. During the event, the sky of Splatsville becomes dark pink and filled with storm clouds, with Grizzco helicopters flying overhead, and the background music is absent. Inside Grizzco Industries, a warning light flashes, and the usual Grizzco lobby music is replaced by a new track performed by ω-3 with the melody of Clickbait. When playing a shift, the battle stage's sky takes on the same appearance, and the background music is a full ω-3 remix of Clickbait.

Rewards
At the end of each Big Run event, exclusive locker decorations are awarded based on the highest team-wide Golden Egg total the player achieved in any one shift. This score is ranked relative to the high scores of all participating players, with different decorations awarded to players whose high score is in the top 5%, top 20%, or top 50% of scores. Players not in the top 50% still receive a basic version of the decoration. 

Badges
Badges are available for reaching each tier of high score in any Big Run event.

Quotes
""Big Run" is a phenomenon where salmon rushes to the area where the squid live. It is rumored that it occurs once every few months. During the big run, the stage you usually use in battle will be the stage of your part-time job."

- Splatoon JP, Twitter

Trivia

 * During the initial Big Run reveal, the sky in the footage was a dark red, matching the appearance of the sky during an Xtrawave. This was most likely a placeholder, as the sky was changed to pink in the second trailer.
 * In the background of a promotional image for Wahoo World, the "seven rings" mentioned in Splatoon 2's Sunken Scroll 17 can be seen in the sky, above an island.
 * Strangely, this detail is not present in game, though the lights coming from the seven rings are still visible.
 * The Sunken Scroll's illustration also appears briefly in the Chill Season 2022 announcement trailer for a few frames at the beginning of the Big Run segment.
 * Players do not have to reach Level 4 to participate in Big Run, unlike normal Salmon Run. This is seen in the stage schedule in SplatNet 3, where it shows a banner reading, "Big Run happening now! Grizzco hiring ANYONE!"
 * The Golden Egg total from a shift will count for the player's high score even if the team fails to complete all three waves, with Mr. Grizz indicating that he cares about the Golden Eggs more than he cares whether Splatsville is successfully defended from the Salmonid invasion.
 * During the Big Run event that took place in Wahoo World from 10 December 2022 until 12 December 2022, players could qualify for the Top 50% by getting 88 or more Golden Eggs in their high score, while Top 20% was 113-136, and Top 5% was any score at or above 137 total eggs.