Mario Tennis Aces

Mario Tennis Aces is an upcoming sports game in the Mario Tennis series for Nintendo Switch set to release on June 22, 2018. It is the eighth installment in the series and will be the first Mario Tennis series game since Mario Tennis: Power Tour on the Game Boy Advance to feature a Story Mode. The game was first announced via a Nintendo Direct Mini presentation on January 11, 2018.

Gameplay
The base gameplay appears similar to that of Mario Tennis: Ultra Smash, featuring different types of shots. Characters have an energy gauge that can be used to perform Zone Shots, Zone Speed, or Special Shots. The energy gauge can be increased by simple rallies or by performing Trick Shots, which require proper timing to hit the ball back. Zone Shots can be performed upon reaching a star icon on the ground, and allow the player to aim their shot anywhere on the court using motion controls. The longer they take to aim, the more energy it depletes. Zone Speed allows the player to slow down time to allow them to reach a far-off shot in time. Special Shots are performed like Zone Shots, but require a full energy gauge. Zone Shots and Special Shots are able to damage rackets. Rackets can withstand three Zone Shots or one Special Shot before breaking, and after being broken they are replaced with a new one, forcing the player to retire when they no longer have any usable racket. With proper stroke timing, the shot can be blocked, increasing the character's energy gauge and protecting their racket from damage. In doubles, each pair shares one energy gauge. Unlike Mario Tennis: Ultra Smash, there will be a left-handed option for characters.

Other than the base style of gameplay, the game will also include a "simple rules" mode which excludes the new types of shots, as well as "Swing Mode", which allows the player to use motion controls to swing their racket, similarly to . Unlike Mario Tennis: Ultra Smash, the game will feature a traditional Tournament mode where the player can challenge computer opponents. Online multiplayer is also supported for up to four players (friends or other players) as well as for online tournaments. Participating in these can provide the player with participation prizes, including special in-game outfits or additional playable characters.

Exclusively in Swing Mode, players can challenge a decision that the ball was shot out of the court.

Adventure Mode
The game also features a story mode set on an island, which includes various challenges for the player to complete, such as missions and boss battles. The story appears to focus on Mario (partnered with Toad) as he tries to rescue those that have been possessed by a dark force, whose energy is imbued in a special tennis racket called the Lucien. The possessed characters take on a mummy-like appearance with glowing eyes, and their souls are taken by the dark force. To rescue them, Mario has to go around the island and complete challenges given to him by various Mario franchise enemies, like Boos and Petey Piranha, in his attempt to locate the five Power Stones that power the racket before Lucien does. Wario and Waluigi heard the myths of this powerful racket and wanted it for themselves, becoming corrupted by its power. Aster, who resides in the Temple of Bask, tells Mario of his objective and teaches him the skills needed to restore peace to the island. Along the way he can obtain different rackets that have different attributes, as well as level up his own stats such as running speed. Should the player's rackets all break, they will receive a game over.

The level selection appears to be based on that of the New Super Mario Bros. series, with red circles indicating an unfinished level and blue circles indicating a completed level, with the name of the level being shown when Mario stands on one.

Marina Stadium

 * Marina Stadium

Bask Ruins

 * Bask Ruins: A Bone to Pick
 * Temple of Bask: An Ancient Trial

Piranha Plant Forest

 * Piranha Plant Forest: Pipe Gripe
 * Forest Practice Court: Rally Challenge (Beginner)
 * Piranha Plant Habitat: Rapid Fire
 * Forest Edge: Sure Shot Challenge (Beginner)
 * Ancient Altar: Forest Monster
 * Bay Ferry: Battle Boat

Mirage Mansion

 * Mirage Mansion: Malicious Mirrors
 * Mansion Practice Court: Panel Challenge (Beginner)
 * Reflection Room: The Great Mirror Mystery
 * Detour: Rally Challenge (Intermediate)
 * Royal Chamber: All Hail the Mirror Queen

Snowfall Mountain

 * Snowfall Mountain Station: Snowball Fight
 * Snowfall Mountain: One vs...One?

Savage Sea

 * Savage Sea Coast: The Sort-Of Sea Monster

Possibly playable
Alongside all the above characters, Dry Bowser was reportedly found in a datamine of the demo. Also, his emblem can be seen on a few of the in-game advertisments.

Bosses

 * Petey Piranha
 * Gooper Blooper
 * Madame Mirage
 * Snow Ogre
 * Whomp
 * Bowser Statue
 * Dark Luigi
 * Bowcien

Non-playable characters

 * Piranha Plants
 * Lakitus
 * Biddybuds
 * Yoshis
 * Little Birds
 * Rabbits
 * Fire Piranha Plants
 * Munchers
 * Piranha Creepers
 * Ant Troopers
 * Conkdors
 * Dry Bones
 * Kleptos
 * Peepas
 * Bob-ombs
 * Spinies
 * Mechakoopas
 * Monty Mole
 * Lumas
 * Parabones

Audience members

 * Toads
 * Shy Guys
 * Koopa Troopas
 * Koopa Paratroopas
 * Hammer Bros
 * Sledge Bros
 * Goombas
 * Paragoombas
 * Penguins
 * Stone Spikes
 * Fire Bros
 * Boomerang Bros

Unknown

 * Aster
 * King Bask
 * Lucien
 * Boom Boom
 * Shy Guy
 * Kamek

Courts
Like in Mario Power Tennis, some courts contain hazards that can be toggled on or off.
 * Marina Stadium (Hard, Clay, Grass, Night)
 * Bask Ruins (a court set in desert ruins)
 * Piranha Plant Forest (a court set in a forest - Piranha Plants can eat the ball to change its direction)
 * Snowfall Mountain (a court set in a snowy plaza)
 * Mirage Mansion (a court set in a haunted house)
 * Savage Sea (a court set on an airship flying over a sea, apparently themed after New Super Mario Bros. U)
 * Inferno Island A court with hexagonal tiles, featuring Mechakoopas and Bob-ombs

Demo and pre-launch online tournament
Prior to the game's release date, a free demo was released on the Nintendo eShop on May 24, 2018. This demo includes a pre-launch online tournament, as well as the ability to practice with CPU players. The tournament allowed players to play as Mario, Peach, Yoshi, and Bowser, with Waluigi, Toad, Spike, Rosalina, and Chain Chomp becoming available as players earned points, for a total of nine playable characters. All tournament participants could receive an alternate costume for Mario that dresses him in his usual clothes (effectively making him appear identical to his appearance in Mario Tennis: Ultra Smash), usable in the full game.

References to other games

 * Mario's Tennis: This is the first time in the Mario Tennis series since this game that Mario and Luigi wear short-sleeved T-shirts and shorts and athletic shoes instead of their casual shirts and overalls and brown shoes. However they wear visor versions of their signature caps while in Mario's Tennis they wear their casual caps.
 * Super Mario Sunshine: The sounds that Piranha Plants make are reused from this game.
 * Mario Power Tennis: The sound Chain Chomp makes is reused from this game. Many characters' voice clips from this game are reused for their Special Shot animation.
 * Mario Party 6: Mario's artwork from this game is reused on one of the large banners.
 * Mario Party 8: Chain Chomp's artwork on the character select screen is from this game.
 * Mario Party DS: Wario's artwork from this game is reused on one of the smaller banners.
 * New Super Mario Bros. Wii: Boo’s artwork from this game is reused on one of the smaller banners.
 * Mario Party 9: Koopa Troopa's artwork on the character select screen is from this game.
 * New Super Mario Bros. U: The Koopalings' airships appear from this game. The large claw arm Bowser Jr. uses for his Special Shot also first appears here.
 * Super Mario 3D World: Several enemies from this title appear in the background of the courts, such as Piranha Creepers and Conkdors. Rabbits also appear and retain their design from this game.
 * Mario Golf: World Tour: Several of Rosalina's voice clips, provided by her former voice actress (Kerri Kane) are taken from this game.
 * Mario Party 10: The artwork on the character select screen for Rosalina and Spike are from this game.
 * Puzzle & Dragons: Super Mario Bros. Edition: Artwork of Luigi and Yoshi from this game are reused on one of the smaller banners.
 * Mario Tennis: Ultra Smash: Marina Stadium bears a striking resemblance to the stadium found in this game. Character models, animations, and voice clips are reused from this game. Yoshi's artwork is also recycled from this game.
 * Mario Party: Star Rush: The artwork on the character select screen for Luigi, Waluigi, Daisy, and Blooper, as well as the artwork for King Boo (used for Boo), are from this game.
 * Mario Party: The Top 100: Wario's artwork on the character select screen is from this game.