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From top of the world to top of the gaming world, Dean Hall has done it all.
The 32-year-old climbed Mt Everest last year and last month sales of his computer game, DayZ, topped one million.
More than 142,000 copies of the game were sold online for $US29.99 each (about $NZ36 at the time) on the day it was released in December.
Sales of a million copies were recorded by January 14, less than a month after it was released and without marketing and with the game not yet ''feature complete''.
Mr Hall, formerly of Oamaru, and now living in Prague, said the growing success of the game had made him determined to produce a ''great'' final product.
DayZ puts players into the fictional post-Soviet world of Chernarus, where an unknown virus has turned most of the population into zombies.
Players are part of a vast online world, where they can join up or fight with other online players.
It was the unstructured nature of gameplay which made it appealing, Mr Hall said.
''I've described it in the past as almost an anti-game, in that it breaks many of the typical rules of game design,'' he said.
''There is no real sense of balancing or an effort to make problems solvable.
''The situations are presented to the players and it is up to them to make the best of it.
''This makes the world and the situations which occur very compelling and give them meaning.''
As the game was unfinished, players were involved in its development, which would continue for about a year, he said.
The game had gained so much attention it even caught the eye of rapper Jay-Z.
''During the early stages of the DayZ trademark registration, Jay-Z's lawyers requested the application be changed,'' Mr Hall said.
''DayZ was also trending very highly as a search term at the time, at times typing JayZ was showing DayZ videos higher [on the search list].
''We just said that we didn't feel there was confusion and that we weren't going to change the application. It was no big deal, but it was a bit of a laugh.''
Mr Hall previously served in the Royal New Zealand Air Force and the New Zealand Army and these experiences had provided some of the inspiration for DayZ.
''While on my survival training in the Brunei jungle, I was captivated by the emotional changes and situations I experienced.
''But I figured there had to be a better way to experience these than exposing soldiers directly to the dangers,'' he said.
''I then decided I wanted to make something more survival-oriented.
''I ... ended up showing them to my commanders in the army. Some were really impressed, but overall I think it was considered a bit far-fetched.''
Mr Hall was recently back in Dunedin visiting family and it reminded him of how much he loved the lifestyle.
''As much as it's exciting to work overseas, I can't wait until I'm back in New Zealand permanently.''
He hoped to open a video gaming studio in the South Island in the future, he said.
''I think New Zealand is a massively untapped industry for video games,'' Mr Hall said.
''Video games like DayZ cost very little to develop, and generate hundreds of millions of dollars. They require no manufacturing, just the imagination and skill of those making them.
''I think video-game development could be a bigger success story for New Zealand than films, if given the chance.''