- "Our cause will live on, to be taken up by others that follow. Ready all cannons. We're going out in a blaze of glory."
- ― Adler
In late 2010, the Osean Federation's Arkbird spacecraft was sabotaged and later boarded by Belkan operatives. At some point, Adler joined the Arkbird's crew and participated in the repair efforts. Unbeknownst to the Osean astronauts, however, Adler and his comrades secretly modified the Arkbird and installed UCAV launch-ports on its ventral hull. Sometime between December 10–19, a V1 tactical nuclear warhead was secretly loaded onto the Arkbird via SSTO launch. With the Oseans' help no longer required, Adler and the other Belkans seized control of the Arkbird. During this time, Adler communicated with and received orders from "Schenze", a fellow Grey Men operative stationed in Sudentor, North Osea.
On December 19, 2010, Adler received a coded transmission that contained the message "N attack by A-Sat on Okchabursk to commence at 14:00 hours". In order to accomplish the nuclear attack on Okchabursk at that time, Adler was directed to steer the Arkbird into the upper atmosphere over the Ceres Ocean at 1300hrs and use air friction to lower its speed. At approximately 1309hrs, Osean astronaut John Harvard sabotaged the Arkbird's controls and fled via an escape capsule.
Adler was eventually able to pull the Arkbird out of its dive, but by then, the Razgriz Squadron had intercepted the Arkbird and opened fire on it. Adler reported to Schenze that the unknown bogeys were likely the "Ghosts of Razgriz" based off the descriptions he had been given by survivors of the Ofnir Squadron. Adler launched the Arkbird's combat drones and ordered all defensive cannons to open fire on the Razgriz.
While the Razgriz were occupied, Adler initiated the Arkbird's booster engines in an attempt to regain altitude and escape the atmosphere. When the primary engines were disabled, Adler activated the Arkbird's combined cycle engines, which were also subsequently destroyed. Losing altitude and realizing the severity of his situation, Adler radioed Schenze and reported that the original mission was impossible considering the circumstances. Adler then initiated the contingency plan: change course and detonate the V1 warhead over Osean territory.
In a last act of desperation, Adler redirected the Arkbird to a southeast heading and fired its central auxiliary booster engine. However, the Razgriz destroyed this engine as well. Adler was killed in the resulting explosion after the fatally damaged Arkbird stalled and crashed into the Ceres Ocean. His final words were "Damn you, Razgriz..."
- "Adler" is the German word for "eagle".
- The ADA-01 ADLER, a variation of the ADF-01 FALKEN, shares its name with this character; it is unknown if the similarity was coincidental or deliberate.