Finally someone that actually knows what they are talking about! tdx is somewhere in the timeline of tb (we just dont know when but considering the fact theres many revived enemies this is most likely the follow up to the events of tb) and calamity is supposed to be a new depiction of the void since Dr. Xenon is also turning people into the eradicators what makes people think she wouldn’t want to also bring back the void. He even has the same cracks and stones on him and the “rock” is the glowing crystal on the void but destroyed (I personally call it his heart but idk if it is)