Hoffer made his Karlsruher SC debut in the opening game of the season, playing 45 minutes before coming off in the first half, in a 1–0 loss against Greuther Fürth. He then scored his first goal for Karlsruher SC on 14 August 2015, in a 2–1 win over FSV Frankfurt. This was followed up by scoring in the next game on 22 August 2015, in a 2–0 win over MSV Duisburg. By the end of 2015, he went to score two more goals, adding the tally to four goals this season. Since making his Karlsruher debut, Hoffer found himself in a competitions over a striking position with Pascal Köpke, Dimitrij Nazarov, Dimitris Diamantakos and Vadim Manzon and played under Manager Markus Kauczinski in a 4-4-2 tactics. However, Hoffer soon found himself out of the first team, spending time on the substitute bench. Hoffer finished his first season at the club with 28 appearances and four goals.