It's dismissed out of hand by some as the preserve of "geeks" with latex swords, but those who love live-action role-play describe it as a form of interactive storytelling, writes Peter Ray Allison.

Li swings his sword to the left with a roar, striking a deadly blow to the charging pirate, before engaging another black-clad pirate on his right.

Chaos ensues around them, as the Militia Guild battle with marauding pirates. Li's sword hammers on the pirate's shield. Lunging forward, the pirate's sword slashes across Li's chest armour, causing him to stagger back. Snarling, the pirate moves in for the kill, only for Li to step aside at the last second and take him down with a blow to the back.

In reality, of course, this didn't really happen. But in the fantasy setting of The Gathering, held at Derbyshire's Locko Park, it did.

Every summer thousands of people attend live-action role-play festivals across the UK. The largest, with about 3,000 attendees, was The Gathering, organised by the Lorien Trust.

The rules The game is composed of factions and guilds

Factions are like nation states and are labelled 'unicorns, wolves, bears, tarantulas' etc

They engage in combat - sometimes with each other, sometimes with other players dressed as monsters

Guilds are independent parties - they are neutral and perform specific functions - the Militia Guild, for example, adjudicates disputes

Each hit to a limb or chest counts as one point

Once a player has suffered a number of hits, their score hits zero and they declare themselves injured or unconscious. They can then be helped by 'healers'

Referees are present to make sure that no-one oversteps the rules, to maintain health and safety standards and to answer any questions

Live-action role-play, or Larp as it is more commonly known, sees participants physically playing a character of their own creation. They view it as "interactive storytelling" or free-form amateur dramatics.

The stereotypical perception of a Larp festival is a muddy field filled with nerdy young men squealing: "I hurl my lightning bolt at thee!"

With a fairly equal gender split, the reality of Larp is nothing like this. But, because of such misconceptions, some players do not like to discuss their hobby for fear of ridicule. Those with high-responsibility jobs - teachers, doctors and government employees, for instance - can even worry that misconceptions about Larping might damage their careers.

Players create their characters by spending a fixed number of points on skills and abilities. These include the character's ability to use shields, cast spells that can protect friends or paralyse enemies, or create potions that can heal wounds or cure poisonings.

Most typically based within a fantasy setting, Larp may also encompass science fiction, horror or other genres. One Swedish Larp organisation hired a retired navy destroyer to hold a game based on the Battlestar Galactica TV series.

Larp events vary in duration, from a few hours in an evening to four-day festivals - called fests - held over a long weekend. The numbers vary from twenty players in an evening to several thousand for a Fest.

Media playback is unsupported on your device Media caption Fantasy dressing up for live action role play games

"For most people, this is their holiday," explains Louise Godfrey, a contracting company administrator, who plays the white-robed healer Ma'ziti Kallistama of the Unicorn faction. "They come here to get away from the real world. There's no internet, no phones and no bad news."

The use of phones and other such technology during Larp events is frowned upon, as it is not in keeping for the characters. But some still carry a concealed phone, in case of emergencies.

Michael Rees, a college lecturer, who plays the imposing Captain Darwin of the Militia Guild, says: "Larp is the game you always wanted to play as a child - the perfect game, but with resources, better rules and more fun."

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The stories found in Larp are often martial but also involve investigative and diplomatic elements. The Gathering featured a murder storyline investigated by the Militia Guild (a fantasy equivalent of the police).

The rush of charging into battle with 40 other players against a horde of monsters is an exhilarating experience, as well as an exhausting one when wearing heavy leather armour all day. Combat is calculated such that a wound is gained every time a blow is successfully landed to a part of the body. Each location is able to take a set number of wounds before becoming "unusable".

While Larp weapons are made of latex, it is not unheard of to return home with the occasional bruise.

Although combat is a large part of Larp, less physically capable people are also catered for. "I am physically disabled, but I can still enjoy the social interaction element," explains Lauren Shaw, who plays the green robed and purple horned Hilda Medcalfe of the Healers Guild. "There are a wide variety of people, with different plot teams, so some will cater for people less able to engage in combat."

It can be an expensive hobby - a latex sword can cost £50 and armour can start from £100.

Some Larpers prefer to make their own costumes, and enjoy searching charity shops for second-hand clothing to modify into costumes.

Larp has had its fair share of negative popular culture references - the nerdish Augie, played by Christopher Mintz-Plasse, in 2008 film comedy Role Models, or Gerard in Channel 4 comedy Peep Show. The stereotype is Larpers being socially awkward. Forthcoming horror-comedy Knights of Badassdom, starring Peter Dinklage from Game of Thrones, which follows a group of Larpers who inadvertently summon a demon at a festival, will be keenly monitored by real-world enthusiasts.

Image caption Participants take on characters of their own creation and join one of a number of 'factions' or 'guilds'. The faction known as the Harts prepare for battle. Image caption Live action role-players come from a variety of backgrounds, and can typically be aged from six to 80. Here, players in the Wolves faction line up in full costume in preparation for battle Image caption Field Marshall Wren of the Unicorns faction (central), discusses tactics prior to a battle against the Dragons faction. Larp events vary in duration, from a few hours weekend festivals Image caption Players enact the final moments of a battle. Players buy their costumes and latex weapons from specialist shops, although some prefer to make their own previous slide next slide

Styles of Larp vary from country to country. German festivals can attract up to 7,000 players. Scandinavian countries are noted for taking a more artistic approach, with a greater focus on themes and story-telling, rather than combat.

"Nordic Larp is a tradition that views Larp as a valid form of expression, worthy of debate, analysis and continuous experimentation," explains Jaakko Stenros, game researcher and editor of Nordic Larp. "It typically values thematic coherence, continuous illusion, action and immersion." In the US, Larp is approached more as a sport, reflecting a more competitive culture.

But what does the future of Larping hold? Matt Pennington, from Larp firm Profound Decisions, believes there will eventually be something akin to virtual reality, allowing total immersion within the setting.

In the near future, Pennington foresees dedicated sites designed for Larpers, complete with caves and magicians' towers to explore.

"The greatest thing about Larp is that we are telling stories," concludes Rees. "The joy of Larp lies in those stories being shared afterwards, and the characters living on."

All pictures by Andy Law

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