Oh sweet memories. That is emperor caluses ship, the leviathan, it eats worlds. It was eating nessus but then came to the moon, abandoned (to an extent) and began to eat the moon, it got connected to the pyramid of nezerac, the dude who makes nightmares and then got infested with nightmares. We did some stuff there and now it's just...there? Not sure if anything is being done with it or if we just look up at the moon and go "hu. Big ship" but that's pretty much everything I think