First of all I'd like to say that I'm primarily a home console gamer and as such I have a Wii U to game on rather than a 3DS, however, it comes as no surprise that the platform which has the far superior library is the 3DS so it's really disappointing that Wii U owners don't get the same kind of treatment.
So, on one hand you have a console which outputs [sometimes] great HD visuals but then on the other there's the 3DS with a fantastic library.
[All games below will be in alphabetical order]
Wii U library that I consider worth owning (exclusives & multiplatforms) ~
3DS? While I'll list games I don't own, they're definitely worth playing.
I've to say that I'm displeased going with the Wii U than the 3DS but I was hopeful that the Wii U would've at some point catch up which it didn't. *sigh*
If I were to start from catch I'd go with the 3DS (specifically the New 3DS XL with that bigger screen and 2nd analogue thumb).
So, on one hand you have a console which outputs [sometimes] great HD visuals but then on the other there's the 3DS with a fantastic library.
[All games below will be in alphabetical order]
Wii U library that I consider worth owning (exclusives & multiplatforms) ~
1. Assassin's Creed: IV Black Flag
2. Bayonetta 2
3. Captain Toad: Treasure Tracker
4. Lego: City Undercover
5. Mario Kart 8
6. Monster Hunter 3: Ultimate
7. Need for Speed: Most Wanted
8. One Piece: Unlimited World Red
9. Pikmin 3
10. Rayman: Legends
11. Sonic: Lost World
12. Splatoon
13. Super Mario: 3D World
14. Super Smash Bros.
15. Tekken Tag Tournament 2
16. The Legend of Zelda: Wind Waker HD
17. The Wonderful 101
2. Bayonetta 2
3. Captain Toad: Treasure Tracker
4. Lego: City Undercover
5. Mario Kart 8
6. Monster Hunter 3: Ultimate
7. Need for Speed: Most Wanted
8. One Piece: Unlimited World Red
9. Pikmin 3
10. Rayman: Legends
11. Sonic: Lost World
12. Splatoon
13. Super Mario: 3D World
14. Super Smash Bros.
15. Tekken Tag Tournament 2
16. The Legend of Zelda: Wind Waker HD
17. The Wonderful 101
3DS? While I'll list games I don't own, they're definitely worth playing.
1. Ace Combat: Assault Horizon Legacy
2. Animal Crossing: New Leaf
3. Asphalt 3D
4. Batman: Arkham Origins Blackgate
5. Bravely Default
6. Code Name: S.T.E.A.M
7. Dead or Alive: Dimensions
8. Disney Magical World
9. Donkey Kong Country Returns 3D
10. Dragon Ball Heroes: Ultimate Mission 1 (Japan Excl.)
11. Dragon Ball Heroes: Ultimate Mission 2 (Japan Excl.)
12. Dragon Ball Z: Extreme Butoden (Japan Excl.)
13. Fantasy Life
14. Fire Emblem: Awkwakening
15. Harvest Moon: A New Beginning
16. Kid Icarus: Uprising
17. Kingdom Hearts 3D [Dream Drop Distance]
18. Kirby: Triple Deluxe
19. Lego City Undercover: The Chase Begins
20. Luigi's Mansion 2: Dark Moon
21. Mario and Luigi: Dream Team Bros.
22. Mario Golf: World Tour
23. Mario Kart 7
24. Mario Tennis Open
25. Metal Gear Solid: Snake Eater 3D
26. Monster Hunter 3 Ultimate
27. Monster Hunter 4 Ultimate
28. New Super Mario Bros. 2
29. One Piece: Romance Dawn
30. One Piece: Unlimited World Red
31. Pac-Man and Galaga
32. Persona Q: Shadow of the Labyrinth
33. Pokémon: Alpha Saphire
34. Pokémon: Omega Ruby
35. Pokémon: X
36. Pokémon: Y
37. Professor Layton and the Azran Legacy
38. Professor Layton and the Miracle Mask
39. Professor Layton Vs. Phoenix Wright: Ace Atorney
40. Project X Zone
41. Rayman Origins
42. Resident Evil: Revelations
43. Ridge Racer 3D
44. Shin Megami Tensei: Devil Summoner - Soul Hackers
45. Shin Megami Tensei: Devil Survivor Overclocked
46. Shinobi
47. Sonic Generations
48. Sonic Lost World
49. Splinter Cell 3D [Chaos Theory]
50. Star Fox 64: 3D Edition
51. Super Mario 3D Land
52. Super Smash Bros.
53. Super Street Fighter IV: 3D Edition
54. Tales of the Abyss
55. Tekken 3D: Prime Edition
56. The Legend of Zelda: Majora's Mask 3D
57. The Legend of Zelda: Ocarina of Time
58. Theatrhythm: Final Fantasy
59. Ultimate NES Remix
60. World Rally Championship
61. Xenoblade Chronicles 3D (New 3DS Excl.)
2. Animal Crossing: New Leaf
3. Asphalt 3D
4. Batman: Arkham Origins Blackgate
5. Bravely Default
6. Code Name: S.T.E.A.M
7. Dead or Alive: Dimensions
8. Disney Magical World
9. Donkey Kong Country Returns 3D
10. Dragon Ball Heroes: Ultimate Mission 1 (Japan Excl.)
11. Dragon Ball Heroes: Ultimate Mission 2 (Japan Excl.)
12. Dragon Ball Z: Extreme Butoden (Japan Excl.)
13. Fantasy Life
14. Fire Emblem: Awkwakening
15. Harvest Moon: A New Beginning
16. Kid Icarus: Uprising
17. Kingdom Hearts 3D [Dream Drop Distance]
18. Kirby: Triple Deluxe
19. Lego City Undercover: The Chase Begins
20. Luigi's Mansion 2: Dark Moon
21. Mario and Luigi: Dream Team Bros.
22. Mario Golf: World Tour
23. Mario Kart 7
24. Mario Tennis Open
25. Metal Gear Solid: Snake Eater 3D
26. Monster Hunter 3 Ultimate
27. Monster Hunter 4 Ultimate
28. New Super Mario Bros. 2
29. One Piece: Romance Dawn
30. One Piece: Unlimited World Red
31. Pac-Man and Galaga
32. Persona Q: Shadow of the Labyrinth
33. Pokémon: Alpha Saphire
34. Pokémon: Omega Ruby
35. Pokémon: X
36. Pokémon: Y
37. Professor Layton and the Azran Legacy
38. Professor Layton and the Miracle Mask
39. Professor Layton Vs. Phoenix Wright: Ace Atorney
40. Project X Zone
41. Rayman Origins
42. Resident Evil: Revelations
43. Ridge Racer 3D
44. Shin Megami Tensei: Devil Summoner - Soul Hackers
45. Shin Megami Tensei: Devil Survivor Overclocked
46. Shinobi
47. Sonic Generations
48. Sonic Lost World
49. Splinter Cell 3D [Chaos Theory]
50. Star Fox 64: 3D Edition
51. Super Mario 3D Land
52. Super Smash Bros.
53. Super Street Fighter IV: 3D Edition
54. Tales of the Abyss
55. Tekken 3D: Prime Edition
56. The Legend of Zelda: Majora's Mask 3D
57. The Legend of Zelda: Ocarina of Time
58. Theatrhythm: Final Fantasy
59. Ultimate NES Remix
60. World Rally Championship
61. Xenoblade Chronicles 3D (New 3DS Excl.)
I've to say that I'm displeased going with the Wii U than the 3DS but I was hopeful that the Wii U would've at some point catch up which it didn't. *sigh*
If I were to start from catch I'd go with the 3DS (specifically the New 3DS XL with that bigger screen and 2nd analogue thumb).