But Monster Hunter started out as a PS2 game. It only became a portable series later on. And re-used a heck of a lot of the assets from the PS2 release while doing so. In multiple releases... across PC and home consoles...
The primary audience is on home consoles for those games, but... so what? That doesn't mean they wouldn't pick up a portable game that offered something in their series, if it was compelling enough.
At the very beginnings, I mentioned games could either be ports, or continuations, or expansion packs.. the whole variety of options. The point was to make assets and an engine, and then run with it. NSMB appears to do exactly that.
NSMB is actually exactly the kind of thing I'm talking about though; Nintendo was able to the WiiU with a new Mario of considerable gameplay quality, that felt polished in many ways, because they were not re-inventing the wheel to make it. Started on a portable in 2006, continues to be successful with console releases across 2 home system generations, and even ones back on portable, into 2013 and beyond.
Yet you can be sure it helped system sales, and the Luigi expansion they're making now is a low cost idea that seems poised to offer high returns, and will hopefully expand the concept of what Digital services can do for the WiiU, as well, while also being offered as a retail version.
I agree with Nintendo's overall E3 sentiment; We'll pave the way, and once we prove there's a place for games and publishers on this system, those publishers will jump on board.
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To offer a Sony-centric example, lets say they made a 2.5D metroidvania-style God Of War on Vita, as a system exclusive.
It got people interested in this sub-series. 2 or 3 years later, they bring out a PS4 entry, as an expanded port, with 2 hours of new content, all the graphic upgrades one expects, plus owning this game either replicates the content for the old Vita version, or gives you a new character to play through a prequel-chapter on Vita, that bridges between the 2 games. Vita version unlocks a new character + some challenge maps on PS4 edition.
1 or 2 years later, the series returns to it's original home on Vita, fully new entry, better looking between the improvements learned on Vita software over the time, and able to use much of the higher-quality assets developed during the PS4's game. Much like Rocketbirds recently did with rewarding players of their PS3 full game or Demo, ownership of these previous 2 releases (Through proof on your PSN account/owning saves/whatever) gives exclusive bonuses.
You minimalize backlash by "this game switches system!" due to time spent between games, and rewarding people who have contributed to the series. You're not competing against yourself, because the releases have easily reached their majority of sales by the time the new game is out. Hopefully, more people go back and buy the old one (especially if it's reduced in price by that time on PSN), to unlock the content in the latest release.
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In the end, I guess you can say I love my Vita exclusives, but I don't think it hurts a brand to have some intermediate releases between big sequels, especially because real great sequels take time. I'd be first in line to buy a Gravity Rush 1.5 (with all DLC + Sea Wasp backstory new content) on PS3 or 4, and would be right back for Day 1 of Gravity Rush 2 on Vita.
I wonder how a "The Last of Us" Vita exclusive story would have worked out, for instance...