ScubaV, that was awesome.
I think we just found the very things the Masters are fighting against. Honestly, the only thing that gives me a shred of hope in negotiations is that Ean has the same hunger these things seem to have. But, yeah, unless this floating planet feels extremely beneficent, the negotiations won't be negotiations.
Sacrifices, rope, this wouldn't have made a difference, I think. We were fucked the moment we crossed through. But hey, this was safer than taking a gamble on Vajra, right?
The enemy of my enemy isn't necessarily my friend. Whatever these beings are, they can't cross the rift. I think that they create and use the biomass brought by the Terasphagos to sustain themselves, possibly with the goal of being able to exist in our dimension, the same way the Masters do. Remember that just after it greeted us, the giant sphere created another horde of Terasphagos and told them to stand down. It probably did this to see if we were willing to "negotiate" (i.e. get fucked really badly).
Oh, and why would them possessing the same hunger as Ean be good for negotiations? Devouring entities are generally not one for offering fair deals.
As for B, after reading the update, I'm convinced that it's not a black hole:
You notice that the spheres were gathered near tiny little seams like the one you had entered from. Most of the seams appeared only transiently, forming and dissolving in the fabric of the void before the spheres could send any through, but on occasion, some developed into cracks, and it was towards these that the spheres gravitated.
So our rift in reality is a seam that enters into this mysterious white expanse. This place is sort of like Sigil, with an infinitely vast number of portals leading to an infinitely vast number of worlds. It wouldn't lead to a black hole because it's clear to me that these beings need to collect biomass for some unknown reason. Guys, we don't know where the rift will lead us, but it will probably lead us to another world. If not, we can try to find a way back to our own "seam" in the future.
All I'm saying is this:
given the choice between a certain death/getting fucked over badly and a gamble, pick the gamble. Zapping Marduk with a thunderbolt has made people way too gunshy, so they make stupid decisions that appear safe, but are actually insanely dumb and risky. Sort of like negotiating with an extradimensional being of incredible power on its home plane. Run the fuck away.