Bringing in the mission they abandoned at the start of the story was a nice touch!
This chapter had so much medical stuff happening that, I thought to myself, 'This is like Gray's Anatomy.' I only wish the pun had been intended.

You shift tenses a lot while writing, I'm not sure if you've noticed. It can get a bit difficult to follow.
I'm glad Gray is trying to get used to Lucy's touch. It made me really sad, last chapter, when Erza couldn't comfort him at all.

A demon is stirring, oh no! And our demon slayer is out of commission too! Though, who knows, given all that Gray has been through, there might a Kendra hiding in the woodwork.

I was wondering, given that Wendy's element is air, do you think it would be possible for her to read Gray's words from the tiny exhales he released while moving his lips?

So much to love here! I love Erza showcasing her acting talent. Hilarious.
I do not trust this man, Grog Fot. No one is that nice. I was wondering though, if that little bit of backstory is from the young Gray spinoff manga. I haven't read it yet, but it sounds like something that would fit!
Oh wow, the Arius subplot was so convoluted. I want to say it came together cohesively, but I honestly can't be sure. There were so many twists! I should've probably kept notes as I was reading haha.
Lyon and Gray's BroTP is a delight to read. I loved the little backstory about Gesture Speak!
As for your author's note, I'm really glad you constructed a whole story around that oneshot!

I just started reading this and I'm already loving it!

Oof. That was a kick in the gut. Now Natsu likely feels that it’s his fault for not taking out those bandits. Guess a little rampage will help him blow off some steam, though. Looking forward to more.

Man...poor guy. I’ve felt more than my fair share of pain in life but geez...those injuries will break someone. At least he’s got everyone around him.

I especially love Lyon’s role in all of this, as both mediator and comforter. It’s a new side to their relationship that we never really saw in canon. Usually, their relationship is all quips, but this is new and refreshing.

Love Gajeel and Levy’s little side quest as well. Totally like him to refuse to sit around. He would definitely want to do some shady stuff and act macho instead of twiddling his thumbs at his injured guildmate. Natsu would likely do the same if it didn’t mean leaving Gray.

I know this wasn't your intention because this is a friendship fic but the Gratsu feels are STRONG in this one!
It's going to be a very tough journey for Gray :(. I'm glad he reunited with the team though. That was something that struck me as odd about the previous chapter. That they left him alone. I know Master told them to and that they couldn't have helped him anyway, but this is Team Natsu we're talking about. But then again they didn't keep in touch through the post-Tartaros time-skip so why not? I will remain slightly miffed at them for that though.

I was wondering, is the Key of the Starry Sky arc canon to your story? Because Wendy therapied Erigor in that using her Sky Magic. Made me think of possibilities for the post-seal world for Gray.

A thought: You sometimes have too many characters about. It's a hassle for the writer, I know. You have to find something for everyone to do. But I'm not sure if it's necessary to tell the audience. Or at least, maybe don't tell the audience in a single info-dump paragraph. It's hard to keep track of the players or to remember. Some roles are more important than the others anyway.

(Also side note: You used 'broad spectrum of antibiotics' in the chapter, which is ofc technically correct but is also very very similar to 'broad spectrum antibiotics.' So if you meant the former, I'd suggest not using spectrum.)

I absolutely loved it. Can’t wait to read the next chapter

Interesting and original concept that fits in well with how the show likes to do things, well done. is it bad that I could literally hear Lucy's voice in my head reading those lines, or is that normal? Anyways, I like how you detailed the severity of his condition without having a character explain it in real time, it was a great concept.

Perhaps Freed will be able to help with the seals and then Wendy can stop feeling so down, but who knows at this point. Looking forward to more.

I tend to find epistolary kind of dry, but I think it worked pretty well here. It's a good way to give readers a lot of background about the developing situation and Gray's condition without too much info-dumping or getting caught up in drawn-out explanations. I think it mostly works because it both chronicles the shifts in Gray's condition and tells a little bit about how a lot of characters are handling it and what they're doing. There's some pretty scary stuff in here, talking about possibly permanent eye and vocal damage, drug addiction/medicine issues, etc. I'd just make sure all of those things are addressed in the recovery arc since you brought them up here. It's a good way to introduce the issues.

For whatever reason, I kind of wanted to see the letters dated to give a clearer sense of the timeline. But they do give the sense of passing time, so maybe it's unnecessary.

Anyway, there's a good mix of different focuses and characters and tones, which helps keep the letters fresh. This is one of the better uses of epistolary.

A fittingly FT conclusion to the battle. I have to say I'm a tad bit annoyed by the creature stirring at the end of the chapter. Haven't these poor mages been through enough T_T. Here's hoping it will be a good long recovery arc hahaha. That and it's also way more impactful, as a story, for us to see Gray and the others taking down a baddie post-recovery. Still. I wish these babies could take a vacation T_T.

Great chapter! I'm not entirely clear on the seals. Can they be lifted now that the necromancer has been defeated? Will they cease to function when the wound heals? (But surely such deep wounds would leave scars!) Will the team have to slice into Gray to disfigure the ruins to destroy them (some more torture)?
What I'd love most of all is if you keep Gray blind even post recovery. It's always nice to get some good disability rep. But I'm not sure if you're keen on researching and writing that. I have an eyepatches character in my story and I keep forgetting about it. It's harder than I thought it would be *sighs*. But if you feel up to it, it would be so so cool to see!
The scene between Gray and Lucy over here was also so great. Very emotional. Loved it.
Waiting for the next chapter, where hopefully Gray heals a little bit, the poor baby.

Excuse my language but hoy sh**! That was so cool! Gajeel! That whole scene was epic. So creative and generally badass and awesome!

And then the emotional punch of either goodbye scene. OOOOF? The NaLu feels, the bakama feels, the- why am I still talking I have to go read the next chapter STAT

I loved the bit in the stationmaster's office. Especially Erza's 'I said please, didn't I?' Hilarious and so her.
Ouch poor Gray, he's in so much pain! I honestly gave a huge sigh of relief when he felt his friends' presence. Rescue! Finally!

Some thoughts I had on the torture stuff so far: Gray's been strapped to a grate fora few days. I'm assuming he would have had to piss or poop at some point during that. Idk if you left it off deliberately because you didn't want to humiliate and degrade him, just torture him. It would've definitely contributed to the smells too. It didn't occur to me before I saw 'ammonia' in this chapter.

A thought on the necromancer: He keeps saying he tried to show Gray that Silver was bad guy, except he didn't? He just tortured Gray. A few mind games would have been an interesting addition here. Make Gray doubt the truth (his interaction with his father in canon is... Minimal and antagonistic mostly) about who his dad was. His dad froze a village of Giants coz he thought the Eternal Flame was a demon afterall. So there are a lot of canonical moments that the necromancer could have used to plant the seeds of doubt and actually turn Gray. Along with the torture.

Side note: Wendy's reasoning for staying with Lyon we could have done without. It was excess baggage.

Normally I don't read such dark stories but you've got me on the hook. I feel compelled to keep reading because 1. It's well written 2. You've set up an interesting backstory wrt the necromancer 3. You've done a fantastic job at emphasising the torture, so anyone with an iota of sympathy for Gray is chewing their nails trying to see if he'll make it out.

OK, the sleep potion forensics scene. This is something I struggle with a lot too - how to provide the characters an the audience a sizeable chunk of data without it being an overload. Reading a 200 word paragraph on a new concept is not something most people enjoy. Same with when Makarov is reeling off instructions for the guild members. I don't have a solution for this myself, because the audience needs to know what's going on.
I saw on your profile that you write plays and I'm from a theatrical background too, so maybe that's why we find it easier to put things out there in direct speech.
Maybe it would be easier if it was halved? Half in speech and half in the narrative? And leave out the (honestly very creative details that make you feel happy as an author coz you have answered every what if) details that are not entirely pertinent to the story. Or if they are pertinent, provide them in a later space where they are closer to the characters/action. Last resort, break the paragraph on two. That said, I'm not sure if these are good suggestions because I'm not great with this either.

As for 'graphic or mean' I will say that it does skate very close to the edge of torture porn with how you're treating Gray. But that's a question of taste. Some folx like that and some don't.

I love how you slipped in a smidgeon of backstory for the necromancer in here. I have a lot of theories about him! And about Silver! So curious to see what's going to happen!

'What universe had he pissed on to deserve this?' I felt that in my soul. Poor Gray. Lots of intetesting set up in this chapter, Aakash can't wait for the payoff! I love how you write (style-wise).

You weren't kidding when you said this fic was dark. I thought the sleeping powder was a clever twist and the fight scene was really dynamic. I'm curious about the necromancer's motivations but all in due time I suppose.
I read your other fic as well (the frost festival one) and the writing in this one is a lot better. More cohesive and better flow. I did notice in the last one though that there are some spelling errors in your text, mostly in the form of homonyms (in this chapter, pummel instead of pommel) or letter-swaps (in the other fic obverse instead of observe), which might not be easy to catch if you're using a screen-reader or something similar.

I didn't mean to review here, I usually wait till the end but the sleeping powder made me comment haha. Onto the next chapter!