On May 20, 2013, 18:00 he successfully summited Kangchenjunga together with his climbing partner, 26-year-old Péter Kiss. During the descent Erőss reported feeling weak and showed signs of exhaustion, falling behind the rest of the summiteers. He spent the night presumably alone in the death zone but in the morning he was joined by Kiss, who in a highly unusual move climbed back up to help his partner, as reported around 9 am. They were seen descending slowly towards Camp 4, situated at 7600 m, but soon after Kiss fell and disappeared. Erőss' condition deteriorated rapidly, reporting vision problems, being unaware of Kiss' whereabouts and finally speaking incoherently. He sat down and slept a few hours, after which around 3:00 pm he reported feeling better and seemed to get back his strength to start moving down to Camp 4. Along the way he went missing, and was never seen again. Members of a Korean expedition, who also lost one of their members, attempted to search for both Erőss and Kiss but only Kiss' body could be spotted.