The climber, Dai Koyamada, travelled from Japan to the Swiss alps four times between 2010 and 2012 to work on this particular bouldering problem. Bouldering problems are climbs that don't require ropes because they remain close to the ground, but rank in difficulty between V0 (easiest) and V16 (impossibly difficult)... I, myself, can do somewhere around a V2 or V3 climb... But Dai Koyamada here solves a V16 climb...Notice how, at certain points, his entire body is hanging from two fingertips and a single toe-hook.
It's a long video, so if you get impatient, his final ascent begins around the 12:00 minute mark.
「The Story of Two Worlds low start V16」 from project_daihold on Vimeo.