Barbie, that eternally youthful icon of girlish fantasy, may look like she has all the brainpower of a lobotomised Playboy bunny — but beware. Her smiling plastic-fantastic exterior conceals a core of commercial steel, as any doll who has dared to challenge her supremacy knows to her regret.

Not content with dispatching poor Sindy in the mid-Nineties, Barbie did away with Bratz last year in a lawsuit that saw Mattel (Barbie’s people) successfully sue MGA Entertainment (Bratz’s people) for copyright infringement. Barbie is once again queen of the plastic prom, presiding over a multibillion-dollar merchandising empire: not bad for an ageing bimbo.

She should enjoy her victory while it lasts. For this Christmas there are two new chicks eager to get their manicured mitts on that pink sparkly crown. Their target is a new generation of little girls for whom the saccharine sweetness of Barbie fails to resonate; girls who don’t want to play house, or ride ponies, but who see themselves as cool rather than cute — or so the press release goes.

Two rival companies manufacture the dolls, Liv and Moxie. Spin Master, the makers of Liv (£19.99), have trademarked the phrase “Real Girls, Real Life”, and they hope this relatively wholesome approach will appeal as much to parents as it will to their daughters. Their dolls hang out on scooters or skateboards, and favour casual denim over faux fur. As well as interchangeable wigs, their online personas (every self-respecting toy has its own website and blog these days) have in-built insecurities and “flaws”. Think Barbiefor the Boden generation.

Moxie (from £9.99) is a more straightforwardly minxy affair. Manufactured by MGA, she is effectively Bratz mark two. The oversized, manga-esque eyes and lips remain, as does the improbably thigh-length hair and the vacuous expression. Her motto is “Be true! Be you!”, which mostly seems to involve being a pop star or playing with her hair. Her name, we are told, means courage, energy and determination. Adding to her “modern” credentials, Moxie drives a carbon-friendly small car instead of the SUVs favoured by her ancestor.

The rivals will be slugging it out in a tough market: dolls are worth about 12 per cent of the toy market, at £260 million a year. But even before the collapse of Woolworths — a major seller of dolls — sales had stalled.

Between 2005 and 2007, sales rose a mere £3 million, according to Mintel, the market researcher — a rate of growth that lagged behind both inflation and the rest of the toy market. Worldwide sales of Barbie plunged 9 per cent last year.

Sarah Allen, a spokeswoman for Mattel, said that this Christmas would be the most competitive in years for doll-makers.

“Woolworths had a big impact on the girls’ market — it was a real showcase for the girl’s sector and dolls have not seemed to have found the same home that boy’s toys have.”

As well as competition from rival dolls, toy-makers are fighting for attention amid increasing demands on children’s play time.

“Our universe is much bigger than our direct competitors — music, fashion and electricals are all competing for playtime”, Ms Allen added.

Appealing to parents is crucial for this pre-teen market. While advertising and peer pressure all contribute to a doll’s desirability, most children still require parental participation to purchase one. Mattel’s Barbie Fashionista targets the “girl-requested, mum-endorsed” market and Liv comes with the approval of a parenting and child development expert, Eileen Hayes.

There’s no escaping the fact that the main mission of Moxie and Liv is to make as much money as possible for their manufacturers. Whoever the winner is, she had better watch out for tall blondes with unfeasibly small feet.

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