At the time of his disappearance he had climbed 10 out of the 14 eight-thousanders, all without supplementary oxygen. As of October 2019, this achievement tied him with Atanas Skatov as the Bulgarian altitude climber with the highest number of successful ascents of peaks over 8000 meters. He was the first Bulgarian to summit four of those mountains: Gasherbrum I (2009), Kangchenjunga (2014), K2 (2014) and Manaslu (2015).