DC97
[10] Knight
The cloven were mentioned in the first one as mutated humans who hate humans but hate chimera more. They eat flesh and consume their dead. It was in an intel somewhere in the level where you have to go up a small hill where there are chimera in pits and buildings (It was towards the beginning of the game).
In the second game Malikov says that the Cloven were merely his experiments gone wrong kind of like Jordan Shepherd (Daedulus) except much worse. I believe the artifact you were thinking of was an artifact of "Pure" Chimeran origin. The "Pure" have been unknown to us up until this game (Specifically Daedulus's words he says to Hale " Can you hear them? They are calling, it is beautiful." Then said again by Hale at the end of the game. But before that Daedulus says something along the lines of "No more humans, No more Chimera, only the Pure".
What this means, we won't know until R3. Until then all we can do is speculate.
