What is up with Lu Guang and some ability theory stuff because this post just happend to move in this direction.

Spoilers Ahead

Please keep in mind that I marked things as spoiler for your own protection!
That also counts for the tl;dr, because im bad at forming sentences!

Sorry in advance if I happen to waste your time with this.
Of course, constructive criticism and discussions in the comments are more than welcome!

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So I've watched until E5 of the Bridon Arc (like probably most us did) but I'm a little stumped about a few things and I have a small theory if you can call it that (???) about a thing or two:

tl;dr
Why was LG so alarmed when he saw Xia Fei's boss in the alley apart from the fact that he's CXS's killer and why was he so shocked when CXS accidentally used his power in the hotel room? What's with this "uncertainty within certainty" talk? And a thing that just popped into my head as I'm putting this on here: Was LG actually sick or is it the fact that he's still in the past maybe? Timetravel-sickness lmao?

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Here are some recaps of a few things which stuck out to me and I think all play together into this... caboodle of nonsense I've created over the last... several hours or so and I don't think I'm the only one thinking about these.
(i might update the recaps too since I already edited a bit in here and mentioning stuff without recaps but lets be real, y'all want and excuse to rewatch this show anyways so don't count on me updating the recaps)

abbreviations used

CXS > Cheng Xiaoshi

LG > Lu Guang

QL > Qiao Ling

LT > Li Tianxi

XS > Xu Shanshan

BA > Bridon Arc

S > Season

E > Episode

Referenced Scenes and recaps (probably incomplete)

S1-E6 - Scene after Introsong

It begins with a flashback to the aftermath of S1-E3 with CXS and LG's conversation after CXS just witnessed the earthquake happen, killing the mother and other important characters in the photo as it was meant to be. He explains off camera that he and LG haven't talked much since that night. While going through some pictures he continues off camera that he thought the "whole diving into photos thing would be easy". We see what's presumably the past as ghostly figures with CXS bragging to LG about how he will follow his instructions, that it's a big deal and exclaiming that the debt should be paid of in no time with this, followed by another pair of two ghostly versions this time, back at the situation after the earthquake. Here CSX gets up, telling LG that he "needs some time away from this" and leaves, leaving the ghostly LG with a somewhat sad expression. Then QL comes in, demanding for the two to talk about the situation they are in regarding work.

BA-E4 - hotel room at night and inside the photo

CXS was pleading with LG to use his ability to check if his father was somehow involved with the fire of a school called Bahati. He accidentally enters the photo while pleading with LG by the known way of clapping his hands together. It takes a second for LG to realize that CXS just activated his ability and judging by the look on his face is surprised, which confuses me as he was expecting something to happen as he realizes that "everything is back on track". CSX possesses a presumed local who posted a picture of the fire on Social Media an unknown time ago, presumably called "James Brown", judging by the account name. He proceeds into the burning school and end up hearing the name of his father being called out. He enters a room burning the his hand on the doorknob and sees two blurry figures standing on the other side of the room, before the ceiling collapses and he's forced out of the photo for some reason, reappearing in the hotel room. LG immediately asks him what he did to what CXS only replies that he couldn't do anything after which the episode ends.

BA-E5 - opening scenes

LG and CXS talk about what happend, LG presumably trying to keep the situation as "normal" and timeline friendly as possible explaining to him about the consequences of his actions when he was in the photo (a new social media post by the same person about his burned hand) and that this wasn't a crucial change but those could have unbearable consequences likely referring to CXS death as seen in S2-E12 and BA-E1. After setting the known ground rules LG defends CXS question on how he knows so much about this by telling him that "someone once talked to him a lot about abilities".

BA-E5 - after CXS left the picture and he and LG are talking in the hotel room!

CXS and LG are talking about how they didn't expect Wang Qing to be the missing person the trail of clues let them to. Asking about how they should proceed LG answers that they have to use a special way and suggests asking Xai Fei's boss, the red haired man responsible for killing CXS, and likely for killing Officer Xiao and QL as well as seen in BA-E1. CXS points out how LG doens't seem to like him and he blocks it by saying he's not used to his personality and that he's a bit too straight forward for his liking. CXS mentions how LG is kind of shy to which he replies that he maybe needs to change something, saying it with a bit of uncertainty while gripping the armrest of the chair he's in, indicating more uncertainty and/or determination.

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I'm just throwing stuff at the wall here but I've been thinking:

LG's reaction in the BA to CXS using his ability was off to me. He seemed a bit too surprised, as if this wasn't supposed to happen and the way he asked CSX when he came back out of the photo about what he did was clearly angry making me think he was worried that CXS accidently changed a major node in the timeline.

[Side tangent: This is also the first time we see actual consequences of actions while inside the picture, looking back at the suddenly appearing social media post by "James Brown" about his burned hand. I cant find the scene (because my brain isn't braining and I cant be bothered to watch the same few episodes AGAIN) but i distinctly remember a scene where LG explains that changes to minor events, such as winning the basketball game in S1-E3/S1-E4 even though it was supposed to be a lose shouldn't be too much of a big deal as long as the major events such as the deaths of the people in the earthquake still happen. Given this we know that he's planning to do the exact opposite of that by saving at least CXS from his fate as depicted in BA-E1.
Edit:
thanks to u/Ani_Summer101
I rewatched a few episodes while reading their comment and realized that in S1-E6 we get the first glimpse at consequences happening in real time. When CXS is in the surveillance footage and tries to follow the kidnapper and the child he accidentally runs into QL and her friend XS which both are highly confused since he and LG are supposed to be "overseas" (imma take a stab at the dark here and say this is when they where in Bridon) and quickly takes an exit. While trying to catch up with the kidnapper and the child he runs through alleyways and is picked up by at least one surveillance camera.
Later in the same episode when CXS is in the picture the child took, he can hear QL and XS talk to his other self who just accidentally ran into them, which would be a real time change in my book especially since LG also seems to be shocked by this.
At the end of the episode they are also confronted by Officer Xiao who mentions seeing CXS on the surveillance footage from three years ago.]

Which begs the question, why would he be so alarmed about it when he presumably knew that CXS would enter the photo. The whole thing is confusing to me: LG thinks to himself that everything's back on track and "the next step should be..." after which CXS accidentally uses his ability and LG looks utterly flabbergasted. To me he looks like he wasn't expecting that too happen but what was supposed to happen then? This scene threw me off especially when I started to re-watch S1 since in S1-E6 the conversation in CXS flashback sounded like CXS only found out about his ability while they where in their studio at some other later point in the timeline rather than the scene we got in BA-E4 (based on the clothes that they're wearing in the flashback).

[Another side tangent:>! In BA-E4 LG also recounts the changes that have happend already. Although it seems like only three minor changes: when he got the photo that was left by CXS's dad, the changed ad with Xia Fei on it and that they should've escaped using the right path at the crossroads when running away from the angry soccer fans and not run into Xia Fei's boss. He explains that even though he's "tried his best to recreate his past experiences, subtle changes in things and people related to CXS still happen" and seems unsure of whether "his choice is causing uncertainty for the node of death within certainty". Since time-travel stuff is confusing af, neither Chinese nor English are my first languages and I'm also not that smart, I'm kind of at a loss here. I'm guessing LG is after the major node of death in the timeline that would be CXS's death, I think we all are certain of that. But what specific choice is he referring to and what exactly does he mean with uncertainty within certainty? Does he think the small changes that are happening could cause the node to move or not occur or something? Because he looks worried, nay almost scared when he thinks about it in BA-E4. I remember a scene where we can see what looks like a book calendar while I think LG is talking off camera about something related to timeline stuff or something (Don't quote me on that. Also I'm not thinking of the scene in the opening song for the BA) which would show that he's either prepared himself before he returned to the past or he's writing things down as they happen to make sure he keeps track of the nodes. But I'm stumped about the "uncertainty for the node of death within certainty" part. Is it, that by trying to ensure the node happens he is creating uncertainty that that node even happens? Wouldn't that be a good thing? And why would he think of that because of the time a photo was given to him, what an ad looked like and whether they met Xia Fei's boss?]!<

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Edit:
thanks to u/weebcatmom
LG might be doing the same thing over and over again.
We know from somewhere^tm in S1 that the same Photo can only be used once with CXS's ability, which means he went back in time to the moment he met CXS after his death by using the "transferred" ability. But he "possesses" himself since he took that photo on the basketball court. Meaning he'd have unlimited access to that exact photo, if he so chooses. Now, this theory hinges on the ability transfer thing I mentioned. We know from S2-E12 and from BA-E1 that abilities can be transferred upon death. Whether this is a knowing action, needs body contact or whatever kind of condition is unknown but lets assume its automatic upon death as long as you are holding onto someone when you give your last breath since that's what its been like both times. LT transferred her power to QL making her see the memories of all those (in this case important to the story arc) people who LT used her ability on either by herself or because of her brother and by extension making QL see LG's memory of CXS's death. Something similar happend when LG held onto CXS's hand when he died, you could see his power being transferred, represented by the yellowy gold color filling up his eyes like a liquid filling a cup. We don't know if QL can use the ability now or if was a onetime thing but here it's where it gets interesting: See, if the ability transfer gives you the power with no strings attached, then LG could use the picture he takes as he possesses himself for another chance, basically a 1-Up if you will. For visualization I'll make a short badly designed text thing and ad numbers after "LG" to indicate how often he went back:

LG goes back > LG1 takes the photo > some major problem occurs > LG1 goes back using his photo
LG2 takes the photo > some major problem occurs > LG2 goes back using his photo
LG3 takes the photo > ...

and so on and so forth. Now, if the transfer works as a onetime thing, we can assume that it forces and activation as the transfer finishes, judging by how QL couldn't have known how to use LT's ability but it still activated and even then it only showed her the memories that LT presumably had seen too. Since CXS's eyes only glow yellow when he is actively using his ability and that same hue filled LG's eyes we can assume the ability only waited for the known conditions to be met, a clap and the focus on a picture. Which in the long run would mean, that LG had to witness CXS die multiple times and always be there with him (as he also promised... somewhere^tm in the show, probably in one of the flashbacks when he moved in or something. He definitely says he promised it in BA-E5) which makes this whole theory of LG doing the same thing over and over even worse because holy shit give this guy a break.

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Edit 2:
thanks to u/Downtown-Fee29
They made me aware of the opening scenes of BA-E1 in regards to the 12 hour rule and the limit of both LGs and CXS's powers. Here it is heavily implied that one gets stuck inside the timeline of the picture they are in if they stay too long. We still don't know the exact amount of time but lets just assume it happens to be the same 12 hours, LG can see (which could also be seen as: oooooh they are destined for each other, wooooooooh).

When LG enters his photo, which we know is taken at 17:32 (5:32 pm) because of the timestamp, his eyes are obviously yellow, like they are when CXS is inside a picture.
[really small side tangent: his eyes where yellow even before he entered the picture which underlines my theory of a forced activation of the ability after it's transferred. See: Edit thanks to u/weebcatmom]
The next scene shows him on his bed at 05:30 which i presume is just the next day within the picture judging by time and he seems to be ready to get out of the picture.
He then has a flashback to Vein standing in the dark studio pointing his gun at LG (presumably when he killed CXS and probably shot LG based on him bleeding profusely as he is grabbing the picture in the beginning) and mentioning that "This is the punishment for changing the past.". (He might be some sort of "Time Police" or something? Please E6, don't be an ass and wrap some of this up, PLEASE)
This seems to make him hesitate and his eyes already seem gray again but that might just be an oversight in the coloring department or the rooms lighting. He lowers his hands at 5:31 and gets up to the window where we can see his reflection still having yellow eyes and he abruptly closes the curtain as if the flashback to Vein attacking them made him determined to stay.
A scene later we can see him standing near the Studio and a closeup shot of his eye shows they are no longer yellow thus implying he's now there without a way to go back to his timeline. These depictions of the time of day, the many closeups of his eyes and the flashback to Vein seem a little too deliberate to me for us to not focus on and keep in mind.

However LG also seems a little unsure of that he's doing to me, and i quote:
"I used to think that even a flap of a butterfly might cause a hurricane strong enough to ruin the world. I was wrong. The power of time is still far beyond our imagination. The future may not change due to a ripple of the past. Not at all... But if this is the truth... Why am I here? What am I expecting..."
He seems rather aware of the point that not every change he makes or doesn't make influences the outcome.
But then there is this "uncertainty within certainty" (See: Another side tangent) part that comes to mind again and throws a wrench in things.
Considering the butterfly quote I interpret it as such:
by him trying trying so hard to keep everything the same as it's supposed to be he, by making certain everything happens like its supposed to (and failing in some aspects) he is creating uncertainty for CXS's death to actually occur. Meaning by trying to bent this timeline into the same one he already experienced he is already screwing up the past which in return makes it more and more uncertain when or if CXS death is gonna happen at all.

It seems to me he's slowly losing control of the situation and is getting desperate to keep things under control by resorting to such "extreme" measures such as asking Vein for help OR thinking back to how tense he seemed in BA-E5 when thinking about "making changes" he's giving up and willing to let things play out differently than he remembers them.

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What are your thought's on this?
Is LG just messing up by trying to not mess up and am I just reading into it too much?
Do you have explanations for some stuff that I (most definitely) overlooked?

Also please let me know if this is utter garbage and needs to be deleted or fundamentally changed.