Mario & Sonic Sports Showdown

Mario & Sonic Sports Showdown is a Mario & Sonic sports game for the Nintendo Switch The game features Mario, Sonic and company competing in six sports: soccer, hockey, handball, basketball, dodgeball, and volleyball.

The game was released for the Nintendo Switch on March 8th, 2021, in Australia and Europe, March 11th, 2021 in North America, and March 15th, 2021 in Japan. The game was also released for the Switch digital download on the Nintendo Switch on the same dates.

Game's Opening
The game's opening begins with Mario and Sonic playing hockey with Luigi and Tails. The four then saw a flyer on the ground that says 'Sports Showdown' on it. Mario, Sonic, Luigi, and Tails ran to their stadiums to start some sports training. In a basketball match between Teams Sonic and Dark, Sonic steals the ball from Shadow and zig-zags passed Rouge and Omega. Tails and Knuckles watched Sonic spin-dash-dunk the ball into the net, making Tails and Knuckles high five. Next in a volleyball match between Teams Rose and Chaotix, Cream and Big toss the ball to Amy and aims it far away from Espio and Vector before Team Rose scored a point. And in a big soccer match between Teams Heroes and Villains, Sonic and Mario passes the ball to Tails then passes it to Luigi who kicks the ball into the goal. Toadette, Toadsworth, Toad, Donkey Kong, Dixie Kong and Diddy Kong are seen playing handball. Toad, Toadsworth and Toadette won however when Mario, Sonic, and their friends saw an airship flying above them. Bowser, Dr. Eggman, Bowser Jr, and Metal Sonic jumped down from the Ship along with Zavok, Zazz, Zeena, Master Zik, Dry Bowser, Boo, King Boo, and Dry Bones, challenging Mario, Sonic and their friends to a Dodgeball match. Zavok throws the ball at Amy, hitting her on the head but Blaze caught the ball saving her health bar. Blaze passes the ball to Sonic who's about to release a whirlwind shot and got all the villains out. Just then, Metal Sonic transforms into Metal Overload and challenged Mario, Sonic and co to a big Basketball game. Tails and Amy passes the ball to Vector then to Sonic. Metal Overlord blocks Sonic's way to the net. While holding the ball, Sonic transforms into Super Sonic as he fly to the net and dunked the ball, making Metal Sonic (and himself) turn back to normal. Mario, Sonic and co then celebrated their victory while Mario and Sonic break the fourth wall by saying "Let's do this" at the camera before the scene ends.

Sports Showdown Ending
The game's ending plays when the Sports Showdown Champion's Cup is completed in Star Tournament Mode after beating Metal Overlord. It begins with Mario and Sonic entering Mario Stadium for a Basketball tournament at night, with Luigi, Tails, Princess Peach, Amy Rose, Princess Daisy, Blaze the Cat, Shadow the Hedgehog, Silver the Hedgehog and co excited over their arrival. Then Bowser confidently arrives for the basketball rematch, with characters such as Dr. Eggman, Metal Sonic, Wario and Waluigi as his teammates. After everyone gets to their positions, all prepared for the re-match, Peach and Amy passes the ball to Sonic and dribbles the basketball then passes it to Mario makes the dunk. As the ball is dunked in the net, the camera zooms in the ball, revealing the hidden words on it, "SPORTS SHOWDOWN!", then the credits roll.

Story
One day in the Mushroom Kingdom, Toad is gardening flowers when suddenly the sky turns dark, and a strange object falls from the sky and crashes. Toad is worried about the situation, so he, along with some other Toads, rushes to the crashed object to examine it. The Toads find six colored crystals: a red crystal containing a basketball; a green crystal containing a volleyball; a orange one for soccer; a pink one for handball; a yellow crystal containing a dodgeball; and a blue crystal containing a coin. While observing the mysterious crystals, the Toads suddenly come up with an idea of introducing new sports - Basketball, Handball, Volleyball, Soccer, Dodgeball and Hockey - to the Mushroom Kingdom. The Toads also organize tournaments for the six sports. The best players of the tournament earn a prize: one of the six crystals that fell from the sky. Mario, Sonic, their friends, and their foes are ready to play sports and enter the tournaments to find out who are the best players of the Mushroom Kingdom.

When the players' team wins the Mushroom, Rainbow, Chao, Legendary, Flower, Moonlight, Spring, and All Star Cups, and gets to the end of the Star, Planet, Emerald and Champions' Cups, everything seems to be normal. However, in the final round, the Egg Carrier/Bowser's Airship appears and the players' opponent turns out to be Zavok or Dry Bowser in disguise. Zavok/Dry Bowser steals the trophy and jumps onto the Egg Carrier/Bowser's Airship, which prompts the players to follow Zavok/Dry Bowser to get the trophy back. They end up playing against the Deadly Team or the Monster Team, while the Egg Carrier/Bowser's Airship flies through space. When the players win against the Team Deadly or Team Monster, they receive one of the crystals that fell from the sky. The leader of the team then uses it to power the Egg Carrier/Bowser's Airship and take the team back home.

After players receive all six crystals, the crystals merge and turn into a dark, glowing crystal. The dark crystal takes the players to an alternate dimension. In this area, players encounter the Metal Madness, a boss from Sonic Heroes. The players must defeat the Metal Madness before it defeats them. When the players defeat Metal Madness, the dark energy from the dark crystal disappears and turns into a rainbow-colored crystal. The players use the crystal again to power the Egg Carrier/Bowser's Airship to take them back home.

Sports Showdown mode's story is highly identical but the last cups are the Star, Emerald, Planet, and Champions' Cups, except after the players' team defeats Team Deadly and Team Monster in the Planet and Champions' Cups, the six Sports Showdown trophies that they receive will end up merging into a dark crystal. That crystal also leads them to an alternate dimension, where the Metal Overlord is found. Similarly with Metal Madness, players have to defeat Metal Overload before it takes them out. When Metal Overlord is defeated, the crystal's dark energy disappears, and it turns back into a rainbow crystal. The players use that crystal to power the Egg Carrier/Bowser's Airship to take them back home.

Gameplay
Mario & Sonic Sports Showdown features six playable sports, all unique from each other. Players can play either alone with CPU allies, cooperatively with others up to four or eight players, or against one another. Up to eight players can participate; however, they can participate Co-op mode in Vs. mode since it is impossible to have all four players team up. The Joy Con Grip and Pro Controller control style is used as the primary control scheme for the game. However, the players can also use the Joy Con in the horizontal position. Players are able to perform actions through inputting buttons as shown in horizontal Joy Con, Handheld, Joy Con Grip and/or Pro Controller scheme. All sports are played in periods, where, except for volleyball there is a certain time limit to each period. When the time limit reaches zero, players move to the next period and change sides. Excluding dodgeball, points acquired in past periods also add up to the current game's total score. In dodgeball, another period commences when all team players get knocked out.

? Panels return from Mario Hoops 3-on-3, where they serve the same purpose: to provide players with either coins, rings or an item. Unlike Mario Hoops 3-on-3, items are held in reserve rather than players holding them. The more coins or rings players have, the more points they can get when they achieve a scoring. Players lose coins or rings when they get hit by an opposing item, which makes the coins and rings scatter on the floor. However, in dodgeball, coins and rings increase the attack power of attacks. Coins and rings increase the power of hitting the ball and players cannot lose coins or rings from items.

There are also special options that can be adjusted for each sport in exhibition mode, such as turning on and off ? Panels, setting the number of periods and the time limit, and other options which can be specific for each sport. Once the options are set, they do not reset whenever a players turns off the game.

On a side note, there's an option which enables the players to have individual CPU levels and receive commands. However, this option is available only when the CPU level is set to "Easy, Normal, Hard, Expert, Pro, Ace or Maxed".

Basketball
Basketball is played in a similar fashion as in Mario Hoops 3-on-3. Players must score points by shooting a basketball into their hoop in order to win the game. Whichever team has the most points after all periods wins the match. Two points are acquired when the ball makes it in the hoop; three points are acquired when the ball gets shot from the three pointer and beyond or when a special shot is performed. The coins and rings that the players gather along the way are added to their total score. Also in this sport, which is exclusive to this game, there is a shot clock on the bottom-left hand corner of the screen so the characters can shoot within the time limit, just like in a professional NBA game. If they do not shoot before time runs out, the other team gets possession. Players are also able to defend, block, and make dunks in this game in a similar way to the actual sport. If the score is tied at the end of regulation, then overtime will begin. With overtime in this sport, no game ends in a draw.

Soccer
A sport previously playable in the Mario Strikers series. Unlike that series and as in the actual sport, players participate in 2-vs-2, 3-vs-3 or 4-vs-4 matches.

As in the Mario Strikers games and Mario & Sonic at the Olympic Games Tokyo 2020, the object is to kick the ball into the opponent's goal, overcoming the opposing team members and their goalie, who attempts to block balls, within the designated pseudo 90-minute time limit (the speed of the time limit goes up depending on the settings, but generally speaking, having the highest time setting, 15-minute matches, causes the time limit to slow down). Halfway through the match, at the 45-minute mark, players halt the game and are taken to a screen that records the current progress of both teams. Afterward, the losing team initiates the kick, and the game continues, with the team's goals reversed until the 90-minute mark is reached. Whichever team has the most goals by the end of the match wins the game. Whenever a goal is scored, a replay of the shot is shown. Players can skip the replay if they wish or change the angle from which it is shown. The opposing team captains then get possession of the ball and start off in the middle of the field, beginning the play again.

Unlike in those games, however, players have more control options and strategies available to them to accommodate the actual sport's additional rules. For example, players on the defense can attempt to steal the ball in possession from other players via slide-kicks, pressure defending with their team via the  or by themselves with  (per the default Type A control scheme), or by simply running into the ball. Players who possess the ball may attempt to dodge confrontations by sliding around holding  by default. Powerful Special Shots can be performed by the captain and assistant captain when the ball starts to sparkle. Each Special Shot has a unique visual effect that varies with the character. Team captains may also pass the ball using their Special Combo Shot move to another captain when the ball is glowing as well. All actions are tied to a character's stamina, which is represented by a blue arrow above the controlled character. The more a character plays and dashes across the field, the more stamina is lost. Characters who have a lowered stamina bar have weaker passes, shots, and speed. Players replenish stamina when they do not partake in any action.

Note: There are no fouls, free kicks, throw-ins, corner kicks, goal kicks, nor penalty kicks in this sport.

Volleyball
Volleyball is played by hitting a ball without making it touch the ground. Players first start matches by serving the ball, either by ground or by air. The match then proceeds, while the players try to smack the volleyball so it touches the ground. If that occurs, the last team to successfully hit the ball over the net gains a point. When a point limit is reached (the default is fifteen points), the set is won. Players can spike the ball, deflect a spike, and use many other moves that bear resemblance to the actual game. Volleyball also has an out zone, much like tennis: any player who hits the ball into this zone forfeits a point to the opposing team. Volleyball is the only sport in the game that can never have a time limit.

Dodgeball
A Dodgeball game always begins with a jump-ball that is done by Lakitu or Omochao to determine which team gets to attack first. Dodgeball is mostly played by throwing a ball to the opposing team. There are two teams of two, three, or four characters and a pink colored Yoshi on one team and a orange on the other team. Players can prevent a hit by catching the ball. Players who fail to catch the ball or dodge it will lose their vitality. They can prevent this if they catch the ball before it hits the ground, especially if the ball flies upwards. Players cannot catch the ball if they are facing away from them, nor can they catch it if an item is in effect.

Players have a Health Meter and lose a portion when they get hit, except for the colored Yoshi and Egg Pawn, who can never be "knocked out," but cannot leave the box at the back of the court. Players cannot control the Yoshis nor Egg Pawns, unless they encounter the ball, and even then, the only commands that the players can give them is to pass or attack. If players lose all their HP, they are out, and they are sent into their box. However, unlike the Yoshis and the Egg Pawns in the box, they can leave if they damage their target with the ball. Players that do this also get a small amount of their HP regained, but are out immediately if damaged again. However, some alternate route objectives do prevent players who are out from leaving the box; this can also be applied to exhibition matches in the settings.

The first team to knock out the opposing team before the time limit expires wins the set. Additionally, the team who has the most number of remaining players automatically wins when time runs out. If both teams have the same number of players remaining at the end of the time limit, sudden death follows. With this term, no set ends in a draw. In sudden death, the first team to take damage loses the set. On a side note, this is the only sport which has a time limit in which players can set the timer to infinite.

Handball
A Handball game always begins with a jump-ball that is done by Lakitu or Omochao to determine which team gets to get the ball first. There are two teams of two, three, or four characters and a Blue Paratroopa or a Hero Chao one team and a Red Paratroopa or a Hero Chao on the other team. Two teams of two, three, or four players take the field and attempt to score points by putting the game ball into the opposing team's goal. Notable scoring opportunities can occur when attacking players jump into the goal area. For example, an attacking player may catch a pass while launching inside the goal area, and then shoot or pass before touching the floor.

Hockey
A hockey game always begins with a face-off that is done by Lakitu or Omochao to determine which team will get the puck at the start of the period. If a team scores a goal or a special shot, another face-off will take place. The goalkeepers in this sport are Shy Guys and Neutral Chaos, and their color depends on which team they are in. In order to steal the puck, players must tackle each other, which can be achieved by the motion of shaking the  ( in sideways mode) or simply by making a character go in front of the opponent with the puck. Sometimes, a struggle ensues and players must shake their Wii Remote the fastest that they can in order to win the puck over and knock the opponents away. The team with the most points wins and, very much like basketball, this game is played in time limits and transitional periods. This sport uses a Hockey Stick.

Sports Showdown
Sports Showdown is a tournament-only game mode, which uses all of the sports and Star Characters. To unlock it, players must complete all six Star and Emerald Cups and defeat Metal Madness. In this game mode, the sport that is played is chosen randomly for each round. Computer controlled characters are set on Easy, Normal, Hard or Expert difficulty levels, When the players beat the Planet and Champions' Cups, they fight the Metal Overload instead of Metal Madness. Metal Overload has more health than Metal Madness and is harder to beat.

Players can select only characters and costumes that are unlocked in all six sports. For example on a similar manner, recolors cannot be used unless they are unlocked for all six sports as well.

Playable characters
There are forty-two playable characters in Mario & Sonic Sports Showdown; everyone are default. All of them are categorized by four groups: As Mario Hoops 3-on-3, this game is shown to make use of character specific abilities. Prior to using these abilities, there is a meter that needs to be filled (shown on the bottom left and right corners of the gameplay screen). These abilities in question can allow the characters to unleash a powerful move in the variety of sports in the game that can help the players win a game. Each special ability is unique to each character and these moves tend to vary from the sport that players are playing.
 * All-around - All-around characters have average Power, Speed, and Technique. They generally are not weak at any stats, but they are not strong in any either.
 * Technical - Technical characters have more Technique, but less Speed and Power. These characters can better aim their shots.
 * Powerful - Powerful characters have more Power, but less Speed and Technique. These characters have stronger and faster attacks and shots.
 * Speedy - Speedy characters have more Speed, but less Power and Technique. These characters can move faster over the ground.

Note: Star Characters will be unlocked for all the players at once after the Emerald Cup is complete and unlocks the Sports Showdown and SuperStar Characters will be unlocked for all the players at once after the Sports Showdown Champions' Cup is complete.

Speedy Characters
Zavok, Zazz, Master Zik, and Zeena appear as non playable CPU opponents for the Emerald Cup finals and the Champion's Cup finals while Dry Bowser, Dry Bones, Boo, and King Boo appear as non playable CPU opponents for the Star Cup finals and the Planet Cup finals. However, they can appear when players are taking alternate routes.

Alternate colors and outfits
Certain characters have alternate colors that can be unlocked by performing certain objectives. Alternate colors can be used only in the sports that they are unlocked in. To scroll through colors, the players can press the + button on the Joy Con, regardless of the control scheme used.

In tournaments, it is possible for the CPU team to use more than one of a certain character, which is now possible for the players' team, and in exhibition matches. Likewise, if the players' team contains a character who has an alternate color, the CPU team can still use that character's unused colors in tournaments; for example, if the players' team contains Yoshi, it is still possible to see a different color Yoshi in a CPU team. CPUs can use alternate colors of characters even if the player has not unlocked them yet.

Non-playable Characters

 * Metal Madness
 * Metal Overlord
 * Birdo (species)
 * Shy Guy (species)
 * Yoshi (species)
 * Bob-omb
 * Zavok
 * Zazz
 * Master Zik
 * Zeena
 * Boo
 * King Boo
 * Dry Bones
 * Magikoopa(Kamek in the British/PAL Version of the game)
 * Goombas
 * Paragoombas
 * Gold Ghost
 * Koopa Troopa (species)
 * Koopa Paratroopa (species)
 * Lakitu
 * Monty Mole
 * Penguin
 * Petey Piranha
 * Piantas
 * Nokis
 * Toad (species)
 * Spikes
 * Cucky
 * Flicky
 * Pecky
 * Picky
 * Chao
 * Dark Chao
 * Hero Chao
 * Omochao
 * Orbot
 * Cubot

Courts
There are thirty-eight playable courts in Mario & Sonic Sports Showdown. Courts in this game are often based on the courts from Mario Hoops 3-on-3, Mario Strikers or Sonic games, some of them even directly return with a slight redesign.

Each cup holds three courts that can be played depending on the sport. A three asterisk (***) means that the courts are available in the Star Tournaments.

Note: The Star Tournament Courts aren't playable in Party Mode.

Items
As in most Mario and Sonic games, there are items available during the gameplay of Mario & Sonic Sports Showdown. These items are available by touching the available and various ? Panels on the court. Most of these items can struck players to make them lose coins and rings, and all items also affect teammates as well. In the Metal Madness/Metal Overload battle, players can also collect Meteorites from ? Panels. Meteorites can be used in different ways; they can be thrown at Metal Madness/Metal Overload to damage it (like in Dodgeball and Handball). Players can also "dunk" it at Metal Madness/Metal Overload (like in Basketball), or kick it (like in soccer). They can also pass the Meteorite at another teammate. Players must receive it and pass it to another player (Volleyball). By doing this, the SP Bar fills marginally, and the meteorite gains power. Coins and rings can also be collected from ? Panels to give it more power. When the SP Bar is full, and all the players of the team are still in the game, the players can use a Special Shot. This can give Metal Madness/Metal Overload significant damage. When the meteorite falls on the ground, it and its power disappears; players must collect a new meteorite and recharge it.

Exhibition
Exhibition mode allows players to play any one of the six sports and customize the rules of the match from the court selection screen at anytime before the match begins (see Gameplay for more info). From there, players can select any two, three or four of the thirty-nine playable characters and one of the thirty eight compatible courts.

Tournament
In Tournament mode, players can compete for the trophy in the same manner as in Mario Hoops 3-on-3. There are three rounds in the tournament. When players win a game, they move on to the next round of the tournament. Each time players win a cup, they can earn one of the six small crystals that corresponds to the sport's color and the players moves on to the next tournament. If all six cups are cleared for that corresponding sport, then it becomes a Sports Crystal that is placed on the Egg Carrier/Bowser's Airship.

After winning the Star and Emerald Cups of all sport, the player unlocks the Star Tournament Cups in Sports Showdown Mode. Also, if players clear the Star and Emerald Cups at all sports, they receive all six Sports Crystals to power the Egg Carrier/Bowser's Airship. After collecting all six large crystals, they battle Metal Madness and defeat Metal Madness. Sports Showdown mode is unlocked when this is cleared. Sports Showdown has six skill level options, which are Easy, Normal, Hard, Expert, Pro, Ace, and MAX settings, and it is a tournament in which each match is a randomly generated sport. Also, clearing the Planet and Champions' Cups in Sports Showdown mode makes players face off against the Metal Overlord.

Difficulty Descriptions
Easy: "Rookie opponents can let the players win super easy and the opponents won't score points."

Normal: "Enjoy a standard match as you take on slightly difficult opponents in each round!"

Hard: "Test your skills in a more challenging match against advanced opponents."

Expert: "Now your opponents are getting serious! So get ready!"

Pro: "The opponents are getting more tougher! So be prepared!"

Ace: "Intense opponents are challenging to compete!"

MAX: "The world's most hardest difficulty ever in the Sports Showdown! No one ever won against these opponents! EVER!"

Alternate routes
Players can also replay tournaments to find alternate routes, but they must clear the tournament the first time in order to do so. Players can take the alternate route once completing the first round. Then, in the second round, arrows will appear. One arrow will take the players to the alternate route, while the other will keep them on the normal route.

In the alternate routes, players do not play normal matches, but missions instead. If players lose a mission, they can do a rematch. If players win a mission, they may continue on, but the road often splits. Players may choose which way they want to go. These roads lead players to different missions, different events, or sometimes even back to the normal tournament. Once players come back to the normal tournament, they cannot re-enter the alternate routes until they start over the tournament.

Taking right choices or guesses, players may reach the Hidden Final. The Hidden Final is the last mission of the tournament. If players lose this mission, they do not get sent back to the normal tournament, but they can retry the mission instead. If players win this mission, they earn the tournament cup, just like players do in the normal run. The Hidden Final involves completing a task that is usually more easy or difficult than the others, for example, winning a match without allowing the opponent to score even once.

Alternate routes in the Star, Planet, Emerald, and Champions' Cups are slightly different compared to the Mushroom, Chao, Rainbow, Legendary, Flower, Spring, Moonlight, and All Star Cups. If players win some missions in the route, they can travel to the Star and Emerald Roads. If players manage to reach the end of the Star or Emerald Roads, they get a message Star Road Complete or Emerald Road Complete!, and travel back to the normal tournament by jumping on the Star.

Unlike the Mushroom, Rainbow, Chao and Legendary, Flower, Moonlight, Spring and All Star Cups, there is no Hidden Final for the Star, Planet, Emerald and Champions' Cups. Instead, after clearing the Star, Planet, Emerald or Champion's Road, players immediately go up against Team Deadly or Team Monster. Unlike with the normal tournament, however, crystals do pop up during the match; the crystals act like coins and rings, which add extra points for Basketball, Soccer, Volleyball, Handball, and Hockey, while strengthening attacks in Dodgeball.

Graphical changes
When completing sports in Tournament mode, some items in menus of the game change.
 * Once a sport is completed in Normal mode, a crystal marks the sport in the record menu and the ball (or in case of Hockey, the stick since the coin is already gold) turns gold in the main menu.
 * If Sports Showdown mode is cleared, the usual blue background of the main menu turns into a rainbow colored background.

The effects of the background changing to a rainbow and the effects of the ball (or stick in hockey) and unlocking everything are also used if a cheat code is performed.

Party games
In addition to the tournament and the exhibition modes, Mario & Sonic Sports Showdown has six party games, one for each sport. They can be played for up to four players. All Party games have at least two levels.
 * Feed Petey - Basketball
 * Egg Pawn Goalie - Soccer
 * Harmony Hustle - Volleyball
 * Bob-omb Dodge - Dodgeball
 * Spike Smash - Handball
 * Smash Skate - Hockey

Record book
The game does keep track of the player's records for each sport. The records basically go as follows:

References to other games

 * Mario and Sonic at the Olympic Games Tokyo 2020: Some of the male characters outfits (including Toadette, Storm and Wave) are used as alternate costumes in the game and in the Character Selecting screen, some of the icons are reused.
 * Mario Bros.: One part of the menu theme is the sound effect of losing a life from this game.
 * Mario Tennis Aces: Some Character's sneakers are used as part of their Athletic Wear.
 * Mario and Sonic at the Rio 2016 Olympic Games: In the Character Selecting screen, Toad and Wave's icons are reused.
 * Super Mario Bros.: The underwater theme is one of the tunes available in Harmony Hustle. Also, sound effects are reused.
 * Mario Kart 8: Some of Team Mario's voice clips are reused in this game.
 * Sonic Free Riders: Final Factory is used as a court in the game.
 * Sonic Riders: Babylon Garden and White Cave are used as courts in the game. Also, Rouge, Amy, Cream and Blaze have their unlockable outfits in the game.
 * Sonic Lost World: Zavok, Zazz, Master Zik and Zeena appear as bosses in the Emerald and Planet Cup Finals and the Lava Mountain Zone is used as a court in the game.
 * Super Mario Galaxy: Bowser's Airship is used as a court for the game that is replacing the Star Ship from Mario Sports Mix.
 * Sonic Heroes: Metal Madness and Metal Overlord are similar in the game. Also, Seaside Beach is a reference to Seaside Hill and Sea Gate and some stages are used as courts in the game.
 * Mario Super Sluggers: Daisy Cruiser is used as a court in the game.
 * Sonic Adventure: The Egg Carrier is used as a court in the game.
 * Sonic Riders: Zero Gravity: Gigan Device is used as a court in the game.
 * Sonic Adventure 2: Some courses is used as a court in the game.
 * Super Mario Sunshine: Delfino Plaza is used as a court in the game.
 * Sonic the Hedgehog (2006): Dusty Desert is used as a court in the game.
 * Super Mario Strikers: The Konga Coliseum is used as a court in the game instead of DK Dock.
 * Super Mario Bros. 2: The animation used for Toad whenever he throws an item appears to be influenced by how he threw vegetables and other items in this game. Additionally, Toad's classification as a speedy character could reference the fact that he is the fastest character in Super Mario Bros. 2. His blue outfit from this game is also used.
 * Mario Strikers Charged: The Battle Dome, Crater Field, The Dump, Thunder Island and the Galactic Stadium are used as courts in the game.
 * Super Mario Bros. 3: In the underwater theme in Harmony Hustle, part of this game's underwater melody can be heard.
 * Mario Tennis Ultra Smash: Rosalina is wearing the same tennis dress in the game.
 * Super Mario World: The athletic theme is one of the tunes available in Harmony Hustle.
 * Mario Tennis: Peach and Daisy's alternate costumes, called "tennis-wear", is based off this series. More specifically, the design overall is based on the outfits that Peach and Daisy wear for Mario Golf: Toadstool Tour and Mario Power Tennis.
 * Mario and Sonic at the Olympic Games: Some of Team Sonic's animations are reused in this game.
 * Mario Kart: Double Dash!!: Lakitu holding up the ball with a plunger is a reference to when he holds up a sideways traffic light before the intro of the game plays.
 * Mario Hoops 3-on-3: Much of the gameplay mechanics come from this game, especially in basketball. Most stages are also based off this game. The theme of Bloocheep Sea makes a return as one of the songs in Harmony Hustle. Also, in most of the sports selection song, there is the sound of the main theme of this game.
 * New Super Mario Bros.: The design and function of the Mini Mushroom is based off this game.
 * Mario Super Sluggers: Daisy Cruiser returns as a court in this game.
 * Sonic Battle: Amy's Room is used as a court in the game.
 * Luigi's Mansion: A court takes place in a mansion based off this game. The Poltergust 3000 appears as Luigi's special shot.
 * Super Smash Bros.: Donkey Kong has a defensive, spinning move that strongly resembles his Spinning Kong move from the Super Smash Bros. series.
 * Super Smash Bros. Melee: The Green Missile makes an appearance as Luigi's dive in volleyball and dodgeball, and his third consecutive check in hockey. Luigi's dash attack also appears to have been referenced as one of his attacks in basketball, his spike in volleyball, and his second consecutive check in hockey. Also, Bowser's Whirling Fortress move returns as his defense in volleyball.
 * Mario & Sonic at the Olympic Winter Games: The gameplay in Hockey is similar to Ice Hockey from this game. Also, Amy's rose spin is used during her special shot.
 * Mario Kart Wii: Some of Team Mario's voice clips are reused in this game. Also, some item images are also borrowed from this game, such as the Green Shells. Now the Spiny Shell is used as the new item in the game.
 * Sonic & Sega All Stars Racing: Tails' special shot similar in the game.
 * Mario Kart Tour: Some voice clips are reused.

Trivia

 * The Hockey sport in this game is presented as Ice Hockey. However, on every court except Mario Stadium and Sonic Stadium, the characters play Roller Hockey instead.
 * In most countries, the name Hockey is generally used for Field Hockey. However, this variant of Hockey is not playable in Mario & Sonic Sports Showdown.
 * This is Storm the Albatross, Charmy Bee, Toadsworth, Pauline, Dixie Kong, Big the Cat, and E-10000B's first playable appearance in a Mario & Sonic game.
 * Donkey Kong, Vector, Bowser Jr., Metal Sonic, Daisy, Blaze, Toadette, and Toad are the only playable Mario and Sonic characters to not appear on the box art and the title screen.
 * Peach and Amy are also the only characters who appears on the box art and title screen that has a different artwork.
 * In the Emerald Cup and Champions' Cup endings Omochao sees the Egg Carrier with the players heading down to the Awards Ceromony while Toad sees the players heading down from Bowser's Airship in the Star Cup and Planet Cup endings.