Sangrevores are a new type of enemy race for Nemesis: Retaliation. There is no Queen this time - but a mighty "King", an ancient being awakened from a long slumber. Mining scavengers found a mysterious-looking "capsule" created out of non-human bones stacked together as if multiple beings had created this tomb from their own bodies. It was quickly transported to the closest human base for further investigation. This is how it all started.
This expansion introduces a totally new mechanic that can drastically change the semi-co-op experience. During the contact with the King or Blood Spectres, your character might become converted! This can entirely change your secret objective mid-game without other players not being sure about it.
With some of the attacks, you will get special infection cards (added next to your special objective face down) that only you can see. Most of the time, they will be neutral - but sometimes, they can transform you into Hemodyne yourself and shift your objective. Contamination cards are changing. Instead of a standard contamination card that will take a slot - you will actually get some unique ability representing your character getting mutated. This will happen only with contact with Crimson Despot or Blood Spectres.

Those cards will give a toolset for players to increase negative interactions - only if they wish for it. But combined with the possibility of them being turned, it will add new layers of paranoia to the game.