Zodiac

Zodiac is an extremely powerful and deadly weapon that is in the custody of S.H.I.E.L.D..

History
THe origins of the Zodiac weapon are unknown.

The Zodiac first came into they possession of the Strategic Scientific Reserve in 1946 when Agent Peggy Carter single-handedly recovered it from a band of thugs in New York City.

S.H.I.E.L.D. later would label the Zodiac as "destroyed" in order to keep un-friendly factions from seeking it out.

In 2014, a terrorist cell discovered that the Zodiac still existed and stole it from S.H.I.E.L.D with the intention of launching a terrorist strike at the Willis Building in Chicago.

The terrorists were thwarted by a S.H.I.E.L.D. strike team consisting of Captain America, Black Widow and Crossbones and the Zodiac returned to [S.H.I.EL.D custody.

Abilities
The Zodiac is a deadly weapon capable of causing loss of life on a massive scale. It is contained in a small vial that appears to contain a liquid. Whether the nature of the Zodiac threat is explosive or biological is unknown.