At the risk of setting myself up for disappointment, I'm going to engage in some blatant speculation/wishlisting for these rumour engine pictures.
The first one, the skeleton caught in fur - whatever that fur belongs to is clearly much larger than a human skeleton. Could this be a first glimpse of the long desired plastic Varghulf?
The next two are a left and right arm, so lets just pretend they're the left and right arm of the same dude. In that case, we're looking at some sort of abhorrant - by the muscularity & proportions. It's positioned around some stonework - maybe sitting on a throne? In one hand it holds a skull, and in the other a sword, but it isn't weilding the sword, just holding it point down or resting the point on the ground, positioning GW generally uses to indicate a commander surveying the field rather than a soldier. Particularly if the figure is seated on a throne, this could be somebody important, more so even than the Abhorrant Archregent*. Are we maybe finally looking at a proper FEC named character to drive their presence in the overall setting narrative? Maybe the Carrion King himself?
Then again, standing against the latter interpretation, the sword /is/ a bit plain to belong to a mortarch (or even a former mortarch).
* which I'm still mad about - The archregent is a fine model & a strong unit, but the FEC range badly needed expansion so the first thing GW gives them was... a model that effectively obsoletes one of the few perfectly adequate units they already had?