Pity the younger brother. Always dressed in hand-me-downs, always the sidekick, always in big bro's shadow. So it was for Luigi, beanpole brother and comic foil to Mario, the most famous face in games.
Pity him is what Nintendo did back in 2001, when they gave Luigi his brother's traditional place of honour: star of the launch line-up for a new home console. Leading the charge for the GameCube was Luigi's Mansion, a ghostbusting romp in which the other brother won a crumbling pile and had to rescue Mario from its haunted hauls, sucking the ghosts out of it with a modified vacuum cleaner.
But Luigi's big moment didn't quite work out as planned. Although it was a game of immense charm and exquisite polish, it was intimate to the point of feeling too small. Fans who'd been taught to expect a genre-redefining, mind-bending Mario epic with every new Nintendo console were left disappointed. Star Wars Rogue Squadron II had the wow factor and the sales, Super Monkey Ball won our hearts, and Luigi slunk back to his supporting role.
But Luigi's Mansion, it turned out, was one of those games destined to be loved in retrospect. Its originality, humour and sheer painstaking quality stuck in the mind, and it's probably fair to say it's more fondly remembered now than the messy indulgence that was Super Mario Sunshine.
Now, a full decade later and completely unexpectedly, it's back on 3DS - sitting proudly next to a new Super Mario in the line-up and quite comfortably holding its own.
The E3 demo begins with diminutive egghead Professor E. Gadd - inventor of Luigi's anti-paranormal Hoover - sending our hero into a mansion to capture an unusual ghost running amok in the library. A screen in the professor's lab digitises Luigi into his 8-bit pixelated form, sucks him up, and he's spat out of a CCTV camera outside the haunted house.
You get to experiment with the controls while running around the mansion's front yard - a pressure-free playground in the tradition of Super Mario 64's castle gardens. Suck the sheet of a statue of Gadd with R, and then blow its helicopter blades round with L; it lifts up and, like anything else you can interact with, spews out coins and banknotes to collect.
That's about it. With only one circle pad on the 3DS, Luigi can't move and aim separately this time, but after a couple of minutes of clumsiness you won't miss it. Instead of yanking the vacuum around, a prompt appears for you to press A at the right moment to reel in your catch.
You can look up and down, run, and rather pointlessly adjust the camera a little by moving the 3DS while sucking. You also have a 'strobe' - like a camera flash - on the A button. (More about that later.) The bottom screen features a map with a zoom slider.
Like the original, Luigi's Mansion 2 uses a fixed camera. Its tight but lavishly detailed environments - mostly rooms - are actually perfect for the 3DS' 3D effect, creating miniature dioramas in your hands.
There's a breathtaking moment when you enter a long corridor with a mirror at the end, and see Luigi reflected far in the distance; the long view is so much more effective for being rare.