Wagner is challenging for TSV Bayer Dormagen, he is a sports soldier ( rank Corporal ) in the sports promotion group of the Bundeswehr in Cologne ..
He finished 2004 ranked second in the German Youth B Championships 2010, he won at the German Junior Championship. Internationally, he won with the team at the Junior European Championships 2008 in Amsterdam and 2009 in Odense, in 2010 won the German team at the Junior World Championships in Baku.
2009 Benedict Wagner competed in the adult class, he reached at the German Championships silver with the saber team. In 2010 he won at the European Championships in Gdansk bronze in saber individual. At the European Championships 2011, he won along with Nicolas Limbach, Max Hartung and Björn Hübner against the Russian team and won silver behind the Italian team. At the World Championships, the team ended after defeats to Russia and Italy fourth. In 2012 he reached with the team at the European Championships in Legnano bronze.
He qualified for the 2012 Olympics in London, where he reached the second round in singles competition, but there was eliminated against his compatriot Nicolas Limbach with 7:15 hits. With the saber team he reached the fifth place.
In 2012 he won together with Benedikt Beisheim, Max Hartung and Matyas Szabo at the German team championships and finished second in the individual standings to second place behind Nicolas Limbach. In 2013 he won at the German Championships in singles and with the team.