Geyr Kluge, born in Berlin (Germany), is an expert field scientist for Euromind, the European Division of S.H.I.E.L.D.
Preferring to be on field for direct research, Key take the lead of Eurolab, a scientific research team composed by high technical/scientific specialist with super powers, and as a scientist, he show often his disdain for the military metods of his support, the Task Force. Anyway, he also shown many time his respect [and also some romantic innuendo] for the leader of the Task Force, Cornelia van der Valk, a.k.a. Dragonfly.
When the Task Force is ambushed and nearly destroyed into a disastrous mission, Dragonfly murdered along with her teammate Blue Condor, and Iceboy kidnaped, Key accept to be the leader of the new formed Euroforce [composite by Eurolab and the survivors member of the Task Force] to investigate about the reason of the death of his friends and recovering Iceboy.
After the event of the "Europa" story-line, Key and the whole Euroforce have been declared dead for the Euromind, but continue operating as a Cover Team.
All-New Marvel Now
Years after, Key and his friend Tiger, are showned recruiting the Black Knight to form and lead a new Euroforce Team [Avengers World #12]
Key is a genius in many field, which ability have been often compared with that of the mutant Forge, but since he is not a mutant, his intellect may be in the same league with other "super" engeneer such as Iron Man or Fixer.
Inspite being a scientis, he is an action man and often lead his team in battle and even if he is not a militar, Key have shown to have a good physical training, good leadership and tactical skills.
He usually wear an armored body-suit of his own designe for increase his resistence and carry a quite ammount of techno-gadget.