This super hero apparently died during the second world war, was found by the super team called the Avengers and has since served with them in all their incarnations. He has no apparent super powers other than heightened strenght and reflexes and a sheild composed of a super dense alloy

Captain America (Steve Rogers) perfectly matches this description. He was frozen in ice during World War II, discovered years later by the founding Avengers, and has since served with the team. His only 'superpowers' are peak human physical condition and his iconic vibranium shield, not supernatural abilities like Thor or Venom.