As was promised.
To begin with, the formatting work here helps take advantage of the medium in a wonderful way. Separating Edax's dialogue with color gives a straight-forward and easily-digestible way to understand that his words are not spoken aloud, and as such cannot be ignored or put out of mind by El. The line breaks feel somewhat more forced as a stylistic choice, where I feel paragraph breaks were more than enough during the heart of the chapter's climax. They remained unobtrusive to the content, thankfully, and I didn't find them detracting from the quality.
The flow of the chapter is well-maintained, though somewhat in a rush by the halfway mark to avoid becoming overly repetitive. There may have been benefits to allowing the piece to breathe more in places, to chew the scenery and allow the reader to settle into the rhythm of El's 'lose forever' situation. The spacing could use some work, single-line paragraphs work wonderfully as punch-ups but lose their flair with overuse. Don't be afraid to drop meatier paragraphs, your prose where present does a fantastic job.
Your theming in this chapter is spectacular, a wonderful development for El's veneer of passivity to give way to his impulsiveness. It's a difficult line to navigate rewarding a character for that quality, and I think you've captured it well here. Being brash isn't always a flaw, and not all confidence is arrogance. I find the possibilities for El's future development exciting, as he treads in unfamiliar waters where his expressiveness is not quite so heavily bound by his ingrained timidity towards conflict.
The meat of this chapter is clearly in the Dormammu-esque sequence of El's repeated attempts at defeating Edax, but I'd like to quickly remark that Edax's mannerisms seem strangely at odds with themselves, and I couldn't quite gather if it was intentional or not. It fluctuates wildly between menace and manipulation, and perhaps that could be attributed to the vague imprints of fear captured in the inches of ground El captures for himself against the pravum. Regardless, it was somewhat difficult to pin down exactly what Edax's demeanor holds at its core, and its exact feelings towards El.
As for the Dormammu-made-Dark-Souls climax of the chapter, there is an unfortunate feeling of lacking in a few of the lines. There's not quite enough time between El beginning to draw blood and El's hard-won victory to feel like the rest of that journey has been made. There's a lack of fatigue in Edax, or else the fear that trickles in when it at last attempts to barter with El isn't impressed earlier to make it clear that El's victory was not a singular moment, but a long-captured inevitability. It may have been more impactful to add one or two more expanded repeats in order to accomplish this.
All in all, I found the chapter compelling, and as a so-called starting line for El's new existence as a vistra, it serves up a suitable and well-crafted transition from bluster to confidence, and from passive acceptance to active challenge. 9/10