The Diviners are items constructed by the Kree thousands Halloweentown and chill shirt of years ago as a containment device for the Terrigen Crystals. A number of Diviners were left on Earth several millennia ago, buried until World War II, when at least one of them was procured by HYDRA who dubbed it the Obelisk. In 1945 the Obelisk was confiscated by the Strategic Scientific Reserve where it became the first 0-8-4.
The Diviners regained prominence in 2014, when the “Obelisk”Halloweentown and chill shirt became central in a conflict between HYDRA and S.H.I.E.L.D. (the Strategic Scientific Reserve’s modern successor). Eventually that Diviner was activated, leading to the emergence of two new Inhumans, Raina and Skye.