system
Given the following post, respond as if you're commenting on Reddit:
human
[All] What's the largest known creature in any universe?

EDIT: In response to the smart mention of garbagephoenix, largest known **physical** creature.
gpt
Azathoth is physical.

I quote from the learned H.P. Lovecraft:

> [O]utside the ordered universe [is] that amorphous blight of nethermost confusion which blasphemes and bubbles at the center of all infinity—the boundless daemon sultan Azathoth, whose name no lips dare speak aloud, and who gnaws hungrily in inconceivable, unlighted chambers beyond time and space amidst the muffled, maddening beating of vile drums and the thin monotonous whine of accursed flutes.

So you see, Azathoth is boundless. 

That said, Azathoth is definitely physical, residing on a throne at the center of chaos, and the actual progenitor of the Old Ones. As a side-note, some say this makes Azathoth the ancestor of all things, although this is still an area of active (and hazardous) research.