2013 - Super Mario 3d World, The Wonderful 101, Legend of Zelda: Wind Waker HD

2014 - DKC: Tropical Freeze, Mario Kart 8, Bayonetta 2, Smash Bros. Wii U

2015 - Splatoon, Super Mario Maker, Yoshi's Wooly World, Xenoblade Chronicles X

2016 - Legend of Zelda: Twilight Princess HD, Star Fox Zero (pre-ordered)

Bought (and sold) Hyrule Warriors, as well. That's been the only big disappointment on the Wii U thus far for me.

EDIT: 2012 - New Super Mario Bros. U (digital) -- I always forget this game, as it came free with my Mario Kart 8 bundle. It's also the only retail release I own digital. 

2012: ZombiU, Batman: Arkham City, Call Of Duty: Black Ops 2

2013: Super Mario 3D World, Pikmin 3, Lego City Undercover, Batman: Arkham Origins, Deus Ex: Human Revolution - Director's Cut, Injustice: Gods Among Us, The Legend of Zelda: The Wind Waker HD, Rayman Legends, Resident Evil: Revelations, Splinter Cell: Blacklist, The Walking Dead: Survival Instinct, The Wonderful 101

2014: Donkey Kong Country: Tropical Freeze, Bayonetta, Bayonetta 2, Mario Kart 8, Teslagrad, Watch Dogs

2015: Splatoon, Super Mario Maker, Captain Toad: Treasure Tracker, Devils Third, Xenoblade Chronicles X, Project Zero: Maiden of Black Water, Legend of Kay Anniversary, Shovel Knight

2016: The Legend Of Zelda: Twilight Princess HD

sorted by release date:
2012 (3) - New Super Mario Bros. U, Nintendo Land, Zombi U
2013 (3) - Pikmin 3, The Legend of Zelda: The Wind Waker HD, Super Mario 3D World
2014 (3) - Donkey Kong Country: Tropical Freeze, Mario Kart 8, Bayonetta 2
2015 (1) - Captain Toad: Treasure Tracker
2016 (0)

sorted by purchase date:
February 2014 (6) - Nintendo Land, Super Mario 3D World, Donkey Kong Country: Tropical Freeze, Pikmin 3, New Super Mario Bros. U + Luigi U, Zombi U
May 2014 (2) - Mario Kart 8, The Legend of Zelda: The Wind Waker HD
2015 (2) - Bayonetta 2, Captain Toad: Treasure Tracker
2016 (0)

2012 - Mass Effect 3, Darksiders II, Assassin's Creed III, Nintendoland and ZombiU, NSMBU / NSLU

2013 - Pikmin 3, Monster Hunter 3 Ultimate, The Wonderful 101, Lego City Undercover, Super Mario 3D World, Assassin's Creed IV: Black Flag, Windwaker HD

2014 - Mario Kart 8, Hyrule Warriors, Bayonetta 2, Super Smash Bros 4, Watch Dogs, and Donkey Kong Country: Tropical Freeze, Yoshi? (or it is in 2015?)

2015 - Splatoon, Xenoblade Chronicles X, SMM, and Rodea The Sky Soldier

2016 - Twilight Princess HD, Pokken, TMS #FE, Star Fox 0

I can't remember the other games that I've missed.

Still in my wishlist: Captain Toad, Fatal Frame V

Well I didn't buy anything last month, so there wasn't anything to update in February

2014: Nintendo Land, ZombiU, NSMBU, Mario Kart+Zelda WW HD (digital promotion), Mario 3D World
2015: Pikmin 3, Splatoon, Toads Treasure Tracker, Yoshi Wolly World, Deus EX
2016: Resident Evil Revelations, Zelda TP HD

Excluding VC titles but keeping eshop purchases... 8 titles.

2012 - New Super Mario Bros. U, Nintendo Land, Tekken Tag Tournament 2, Zombi U, Sonic Racing, Assassin's Creed III, Batman Arkham City.
Total: 7

2013 - Lego City Undercover, Rayman Legends, Pikmin 3, Wind Waker HD, Super Mario 3D World, Assassin's Creed IV, Sonic Lost World, Lego Batman 2, Lego Marvel Super Heroes, Mario & Sonic Sochi, Wii Fit U, Game & Wario, Splinter Cell Blacklist, Injustice, New Super Luigi U, Wii Party U, The Wonderful 101, Need for Speed Most Wanted U
Total: 18

2014 - Tropical Freeze, Mario Kart 8, Wii Sports Club, Bayonetta, Bayonetta 2, Smash Wii U, Hyrule Warriors, Watch Dogs, Lego The Hobbit, Lego Movie.
Total: 10

2015 - Captain Toad, Kirby Rainbow Curse, Mario Party 10, Splatoon, Yoshi's Woolly World, Super Mario Maker, Project Zero 5, amiibo Festival, Xenoblade X, Lego Jurassic World.
Total: 10

2016 - Twilight Princess HD.
Total: 1

Including eShop and indies would double my purchases. Including VC as well would probably double that total again. 

1. SSB