Nothingness as being-not-at-home, falleness, the anxiety of transcending the world (and so constituting the world as a unity as a distanced observer). To overcome this Nihility would mean a reinterpretation of the world as not a distant whole one leaves and views from afar, nor (crucially) is it to re-immerse oneself in the world as if one could become whole again in a reunion with a primordial past. The world must be exposed for what it has always been: a being.
This is more radical than it seems at first glance, since the concept of world is supposed to be in contrast to the self (the Self which One believes One-Self to Be). To shatter the comfortability of self-assertion as something we or one has, owns, or possesses needs a complimentary shattering of the world as a self-contained whole.
But this is not mutual disintegration, it is a mutual fictionalization and multiplication. There are many selves and many worlds. Only in becoming a singular whole does the process of fictionalization begin. The singularity (along with a complimentary multiplicity) as a different conception of being-one; never entirely alone, it nonetheless cannot resist fictionalization. Robots, cyborg war against humanity…
We are afraid of our world crumbling before our eyes. Machines of desire, abstract machines, flesh machines: these will only run away from us in frantically trying to retrieve something we have lost.