Set in 1983 as a spin-off of the Muv-Luv Alternative series, Schwarzesmarken follows the East German Army's 666th TSF Squadron, also known as 'Schwarzesmarken' or Black Marks. This elite unit specializes in launching unconventional assaults against the BETA forces, focusing on disrupting Lux and Magnus Lux to counter the enemy's long-range capabilities. With unwavering dedication to their orders, the 666th prioritizes their mission above all else, often disregarding calls for help from allies that might divert them, even momentarily. Equipped mainly with MiG-21s, the squadron is led by Irisdena Bernhard, who commands an MiG-21PF as they navigate the intense battleground of warfare.