New Zealand mountaineer Marty Schmidt was one of the country's most successful climbers and spent his life climbing the world's highest peaks, often without oxygen.
He and his 25-year-old son Denali are feared dead, after going missing on Friday while attempting to summit Pakistan's K2 mountain.
Two Sherpas discovered their Schmidt's campsite, 7400m up the 8611m peak, wiped out by an avalanche, after severe snow conditions on Friday forced six other climbing teams back to the mountain's base camp.
Marty, 53, and Denali opted to remain.
Reports from K2's base camp said the pair were "almost certainly" hit by the avalanche on Friday night as they slept in their tent.
New Zealand Alpine Club general manager Sam Newton described Marty as a passionate and enthusiastic mountaineer with extensive experience.
"Marty was a highly regarded professional guide and climber," Mr Newton told NZ Newswire.
"He was arguably New Zealand's most successful high altitude climber."
Marty had been climbing for 38 years and worked as a guide at mountains around the world.
He believed in experiencing the "real adventure" of mountaineering and climbing in small groups with no Sherpas, oxygen, huts or helicopters.
"If you met him once, you were really drawn to his magnetic personality," he said.
"He had a real passion and enthusiasm for the mountain and mountaineering."
Born in the US, Marty moved to New Zealand in 1988 and has been an active participant in the New Zealand climbing industry.
He had attempted the summit K2 twice before to no avail.
"I've climbed a lot of the world's biggest mountains but K2 is the one I respect the most. I've been on it twice without summiting. I'm just called to it all the time," he said before he set out on the climb.
In a post on sponsor Macpac's website last week he said they were hoping to summit K2 on July 28-29.
Mr Schmidt had climbed Mt Everest twice and some of the world's tallest peaks without oxygen, including five peaks of more than 8000m.
He has climbed and guided on the world's Seven Summits (the seven tallest mountains on each continent) many times.
His son Denali is named after the highest peak in North America.
"I love to climb with Denali. It's so much fun. We have a great time for three months. Not many fathers get that kind of time with their grown-up sons," he said before he left.
K2 is one of the most dangerous mountains to climb in the world, with around a quarter of those who summit it losing their lives.
Despite the dangers - which include possibly attacks by the Taliban - Marty was adamant K2 was the mountain he loved the most.