Super Smash Bros. for Wii U was first shown during the E3 2013 Nintendo Direct.

Here's the list of characters announced so far:

• Villager (from Animal Crossing)
• Mega Man
• Wii Fit Trainer
• Mario
• Donkey Kong
• Link
• Samus
• Kirby
• Fox
• Pikachu
• Bowser
• Pit
• Pikmin & Olimar
• Luigi
• Peach
• Toon Link
• Sonic the Hedgehog
• Marth
• Rosalina & Luma
• Zelda
• King Dedede
• Lucario
• Little Mac
• Diddy Kong
• Zero Suit Samus
• Sheik
• Yoshi
• Charizard
• Greninja
• Ike
• Mii Fighters
• Palutena
• Pac-Man
• Captain Falcon
• Lucina
• Robin
• Meta Knight
• Shulk
• Bowser Jr.
• Mewtwo (DLC)
• Duck Hunt
• Lucas (DLC)
• Roy (DLC)
• Ryu (DLC)
• ... and secret fighters

Downloadable content

Stages

Super Mario Maker

• Release date: September 30, 2015
• Price (Wii U): US$2.49 / ¥300 / £2.29 / AU$3.25 / NZ$4.25
• Price (Wii U + 3DS): US$3.49 / ¥400 / £3.19 / AU$4.55 / NZ$5.95

Peach's Castle (64)

• Release date: July 31, 2015
• Price (Wii U): US$1.99 / ¥250 / £1.79 / AU$2.60 / NZ$3.40
• Price (Wii U + 3DS): US$2.99 / ¥350 / £2.69 / AU$3.90 / NZ$5.10

Mii Fighter costumes

Ashley Hat + Ashley Outfit (for Swordfighter)

• Release date: February 3, 2016
• Price (3DS): US$0.75 / ¥80 / £0.69 / AU$1.05 / NZ$1.35
• Price (3DS + Wii U): US$1.15 / ¥120 / £1.09 / AU$1.55 / NZ$2.00

Geno Hat + Geno Outfit (for Gunner)

• Release date: December 15, 2015
• Price (Wii U): US$0.75 / ¥80 / £0.69 / AU$1.05 / NZ$1.35
• Price (Wii U + 3DS): US$1.15 / ¥120 / £1.09 / AU$1.55 / NZ$2.00

Toad Hat + Toad Outfit (for Brawler)

• Release date: September 30, 2015
• Price (Wii U): US$0.75 / ¥80 / £0.69 / AU$1.05 / NZ$1.35
• Price (Wii U + 3DS): US$1.15 / ¥120 / £1.09 / AU$1.55 / NZ$2.00

Updates

Version 1.1.7

• USA: July 18, 2017
• Japan: July 19, 2017
• Europe: July 19, 2017
• Australia: ?

Version 1.1.6

• USA: May 19, 2016
• Japan: May 20, 2016
• Europe: May 20, 2016
• Australia: May 20, 2016

Version 1.1.5

• USA: March 15, 2016
• Japan: March 16, 2016
• Europe: March 16, 2016
• Australia: March 16, 2016

Version 1.1.4

• USA: February 3, 2016
• Japan: February 4, 2016
• Europe: February 4, 2016
• Australia: February 4, 2016

Version 1.1.3

• USA: December 15, 2015
• Japan: December 16, 2015
• Europe: December 16, 2015
• Australia: December 16, 2015

Version 1.1.2

• USA: October 8, 2015
• Japan: October 8, 2015
• Europe: October 8, 2015
• Australia: October 8, 2015

Version 1.1.1

• USA: September 29, 2015
• Japan: September 30, 2015
• Europe: September 30, 2015
• Australia: September 30, 2015

Version 1.1.0

• USA: July 30, 2015
• Japan: July 31, 2015
• Europe: July 31, 2015
• Australia: July 31, 2015

Version 1.0.9

• USA: July 2, 2015
• Japan: July 3, 2015
• Europe: July 3, 2015
• Australia: July 3, 2015

Version 1.0.8

• USA: June 14, 2015
• Japan: June 15, 2015
• Europe: June 14, 2015
• Australia: June 14, 2015

Version 1.0.7

• USA: April 23, 2015
• Japan: April 24, 2015
• Europe: April 24, 2015
• Australia: ?

Version 1.0.6

• USA: April 15, 2015
• Japan: April 15, 2015
• Europe: April 15, 2015
• Australia: April 15, 2015

Version 1.0.2

• USA: January 29, 2015
• Japan: January 29, 2015
• Europe: January 29, 2015
• Australia: January 29, 2015

Version 1.0.1

• USA: November 21, 2014
• Japan: N/A
• Europe: November 28, 2014
• Australia: N/A