Lego City Undercover is a hugely underrated open-world sandbox game. Very funny script, solid gameplay, and once again a ton of charm. Best Lego game released so far.
Monster Hunter 3 Ultimate.
Huuuuuuuge amount of content here. You can easily get hundreds upon hundreds of hours of play out of this game. And the combat in MH really is something else. It's similar to Dark Souls in that it's pretty punishing to newcomers, but persevere and the game mechanics really are sublime. No other game makes fighting giant monsters feel quite as exhilarating or rewarding.
Game And Wario. If you want a party game to play with friends, it really is a surprising amount of fun. Not much value if singleplayer is your thing, but as a multiplayer game that gets a lot of laughs going and has some really wacky ideas, it's well worth getting.
New Super Luigi U. If you're unswayed about the base NSMBU game, NSLU might be more up your avenue instead. It's an 80 level standalone expansion which really escalates proceedings by making things bastard hard. Shorter time limits, more emphasis on speed-runnig, and some really fiendish level design. The NSMB games get a bad wrap around here, but mechanically they are absolutely spot on, and the level design really is superb. Possibly even *whisper* better than the original 2D Mario games *dons flameshield*
Some people will say don't use the eShop. Don't listen to them. On the very rare-offchance that your Wii U does go kaput, Nintendo Customer Services will give you credit to redownload your games. More importantly, if you get the Deluxe, Nintendo has a digital scheme whereby you get 10% credit on every purchase you make through the eShop. If you combine that with the deals you can already get for games (like the 30% off W101 scheme), then it's a pretty sweet deal overall. Great eShop games:
Nano Assault Neo. The underrated star of the eShop. Shin'en are technical wizards, and NAN looks absolutely phenomenal. It's also a really fresh take on the SHMUP genre, combining bullet-hell gameplay with Galaxy style planetoids (or specificaly, cells) to roam over.
Toki Tori 2. I've yet to play this game myself, but it's getting a lot of rave reviews from the community, and seems like it's something well worth checking out if you don't mind games that aren't Dudebro Matur!
Chasing Aurora. Again, not played it myself yet, but from what I hear it's a very simple but very well executed indie game that has a lovely atmosphere.
Trine 2: Director's Cut. Buy it for the visual pron. The gameplay isn't up there with the greats of 2d platforming, but it looks so damn colourful and magical that it really doesn't matter.
Lastly and most importantly: if you were thinking of picking up a Wii U for Bayonetta 2, I
implore you to get Wonderful 101. It's directed by Bayonetta's creator, Hideki Kamiya, and Bayonetta herself is an unlockable character. More importantly, the game is a huge step forward on the sort of hacky-slash brawler action we saw in the first Bayonetta game. Entire essays have been written on NeoGAF about how deep the combat mechanics are, and the game is absolutely stuffed to the gills with content.
It's my GOTY contender so far, simply because purely going by gameplay metrics it is on another level to anything else that came out this year. The fact that the game is essentially the closest we will ever get to a Gurren Langen experience in gaming, and makes the original Bayonetta look tame by comparison, only makes things sweeter. It's going to be looked back on as a huge milestone for the action genre, and if you're into those sorts of games then you
need to play it now.
Aside from all that, you've still got the upcoming games like X, Mario 3D World, Donkey Kong Tropical Freeze, SMTxFire Emblem, Yarn Yoshi, and Mario Kart 8.
Dooooo iiiiiit.