I only managed to have a cursory glance over it, but this sentence caught my eye: '“One Sir, a rumor was spreading that a prospect passed the trial in 3 days breaking the record in half”, he answered knowing that Balta could care less.'
I'm not really concerned - you could in fact say that I couldn't care less - about how prevalent the phrase 'could care less' is in everyday language and on the internet, but given the context, I assume you meant 'couldn't care less'. The idiom 'could care less' might be acceptable on the internet, but outside of slang usage it's incorrect.
I apologise if it sounds like I'm jumping down your throat here, but it's a point that really needed to be made. There may come a time where literature becomes "John was PHSLing but Sam only loled cos he found it funny but not totes funny." but I will fight that with every breath in my body.
Anyway, I'd re-write the goal at the start of your story, or possibly replace it with a short blurb. Don't tell people what you want to achieve with your writing - let your writing do that itself. Instead, tell people a little about what's going to start happening. Grab a few of your favourite books from your bookshelf and read through the blurbs or author's notes to get a few clues as to how you should go about writing one for this story.
The idea is for it to be short and concise, but not final; it needs to be wrapped in an air of mystery that encourages people to read about the person or persons, or scenarios mentioned in it.
It's all well and good to say "In Paul's Adventure, Paul and his friends go on an adventure to Cloudland, a place where everyone lives on large clouds, and Caveland, where everyone lives in caves, in order to defeat Gakhead who killed Paul's family and ate his dog, Ribbons." but it not only reveals the entire storyline, it does so without encouraging anyone to read about how it goes. I know who the villain is, and how they go about trying to defeat him. It also mentions unnecessary details, such as Paul's friends (who can easily be added once the story begins) and the dog called Ribbons (which is a rubbish name for a dog).
What it does do is not reveal how they get to these lands, and it also doesn't say they will defeat Gakhead, or how they can do it, only that in order to they have to traverse these lands.
Now, rewriting that, we could go for: "Paul's world collapsed the night he witnessed the murder. His family torn from him by the hands of a cold-hearted killer, all thoughts of a peaceful life are shattered by a single wish: vengeance."
Very, very short, it reveals only what would have been revealed in the initial chapter or so. Paul is clearly the protagonist, and we are led to understand that he once thought he would live a peaceful life. Why would he think that? It's not exactly normal to hope for a peaceful life unless you've recently led a chaotic one, so is there a darker side to Paul, or a side we might yet see? Could Paul's life before the story be fuelling his thirst for revenge, since surely someone would wish simply for justice?
The killer is mentioned only in passing. We aren't sure if Paul knows who it is or doesn't know. Wouldn't we want to know the name of the person who collapsed our world and shattered our dreams of peace? Not only are we interested in Paul's history and how he'll go about his quest, but we're also interested in who the killer is and what motives - if any - he had. Could the killer be linked to Paul's past? Perhaps, but we won't know unless we read the story.
You could try a longer blurb if very short ones like that don't appeal to you, but don't try to flesh them out too much, or you'll start trying to create unnecessary context, and consequently start spoiling the story. It's also possible to lead the blurb with a quote from the first few chapters, but that's not really doable unless you write several chapters in advance, so it's not really expected of casual writing, which is usually just written chapter by chapter, posted as each one comes.
Now we've got that sorted, let's move on a bit.
If I have a failing - and I do have many - then it's that I despise starting chapters off with 'the'. I've done it once or twice, and hated it every time. Even more than that, though, I hate starting the first chapter with 'the'. I see 'the' at the start of a book, and I close it; my interest flies south for the winter, decides it's quite nice down there after all and invests in a house, finds a wife, and starts a family. Nearly every book which has an opening sentence that starts with 'the' can have that sentence rewritten to not start with 'the'. For yours, that rewrite is as simple as "For once, the humidity of Xavier's rainforests was not the cause of Kenar's sweat". Pre-rewrite, though, I will point out that you need a comma after 'for once', otherwise the sentence tries to take on a new meaning and falls flat since the rest of it wasn't intended for it. The way you've used it is more suited for something like "I shall not need you, for once I am king I will have hundreds of slaves your equal or better!". Read my rewrite of the opening line, first with, and then without the comma and you'll see what I mean about it.
The rewrite also doesn't need to mention the anti-venom. It might be nice to mention it now, but given the next line, allow the reader time to guess why; either they guess it and read on to confirm - and then to read how it came to be so - or they read on to find out the reason - and again, how it came to be so. I included the name of what I assume to be the planet here so that other people will make the same assumption, since without them, the later mentionings of the name could easily be referencing a person. How likely is it for someone to own rainforests as opposed to owning a giant snake or other dangerous animals, or penning a survival guide?
The next line is also grammatically incorrect. For it to work, you need to put 'and' after 'illuminated', and I'd put a comma after 'snake' - so "small beams of sunlight penetrated the rainforest's canopy and illuminated the massive headless snake, whose body twitched even in death" - or change 'penetrated' to 'penetrating' and the same about the comma - so "small beams of sunlight penetrating the rainforest's canopy illuminated the massive headless snake, whose body twitched even in death".
Aside from the grammatical errors, I'd also remove the word 'rainforest' from that sentence. The first sentence already established that it's a rainforest, and so the word 'canopy' should not need clarifying. As a descriptive sentence, it's not exactly all that descriptive. It's sort of setting the scene, but the potential in that sentence is not being tapped into. Looking into a rewrite, we can observe where the potential lies, such as in describing how exactly the beams penetrate the canopy - do they penetrate the canopy, lancing through the leafy cluster like shining lasbolts? Or do small, shifting beams of sunlight infiltrate the canopy, silently slipping through slight spaces between the leafy verdant ceiling to illuminate the twitching, beheaded corpse of a giant serpent, whose scarred, pitch-black scales, each as big as a grown man's fist, glinted and glimmered with deathly beauty, and whose slender ebony fangs as long as a combat knife and coated in vivid red blood, dripped with almost fluorescent yellow venom? The first potential sentence seemed fine; it had a nice simile in it and presented the canopy as a leafy cluster, but the second sentence took it a step further, and described the snake as well as the sunlight and the canopy, and also introduced the venom right at the end.
You could go further still, describing the canopy as a vaulted ceiling of leaves, supported by sturdy brown arched branches projecting from thick columnar tree trunks, but that'd be much harder to write in, and to be honest, some people might even see the second possibility as 'purple prose', description that has gone a bit overboard and is either far too much, or just completely unnecessary, usually because the action it is describing is completely mundane - "he expertly leapt across the rushing stream, alighting neatly on the opposite bank" is fine, hell, even "he jumped across the rushing stream, landing firmly on the opposite bank" would do, but some people may go for something akin to "Flexing his powerful leg muscles, he leapt high into the air, cool wind lapping at his face and arms as he flew. Beneath him the normally calm stream ran like a raging torrent, threatening to consume him should he fall and dash him upon the stones beneath the churning waves, turning him into so many tattered ribbons of flesh and dyeing the stream crimson. The stream posed no threat, however, and like an angel from on high he alighted with a soft thud upon the firm ground on the opposite bank, the stream bubbling and hissing as if to throw curses at him for succeeding." which, to be quite honest, is very much overdoing it. He jumped over a stream; he did not perform a herculean task.
After changing that sentence, perhaps think about Kenar's senses. We have what he's seen, but what about feel? Can he feel the poison in his veins? How does that feel? Is it burning? Stinging? Throbbing? How is he breathing? Is it steady, or is it short gasps as his lungs constrict? You say that he gets the paralysis later on, but what about how he feels now? How about his hearing? Can he hear the whoops and cries of other rainforest animals? Is it eerily silent? Can he only hear his own heartbeat? What about half-heard shouts or screams? Also, what can he taste? Bile? Is he about to be sick? Can he taste blood from the previous combat? Can he simply taste the moisture in the air? What about smells? Does the snake's blood smell funny? Does its venom have a distinctive smell (this would be a nice one to include a slight description of, only to have it reappear later in the story, lending it a sense of continuity and rewarding those readers who linked the two before they are told)? Does the rainforest have any smells? All too often description is left purely to sight-based observations, when there are at least 4 (perhaps more depending on races or powers or similar things) other senses to use. You wouldn't go out one day and just use one of your senses, would you?
I'm going to leave it here for several reasons: first, I don't want to go through the entire thing picking out what is wrong, why, and how to rectify it. I've done the first two sentences, but it's best if I leave you to pick them up for yourself, and get into the habit of re-reading everything you write and being your own best (or worst) critic. That's not to say that you shouldn't ask for help or advice, but it is saying that you should read through everything yourself first and try to poke a few holes. Anything you saw and thought "it'll do", for example, is a prime target for looking at again.
The second reason I'm going to stop is because it's half past 4 in the morning, and I've already spent just shy of 2 hours writing this up.
The third reason is that, looking at this post in Microsoft Word, I've written enough for this to be considered a short story in itself rather than an advice post, and it might be easier to let everything sink in as opposed to starting off every other paragraph with "And another thing..." and bombarding you with information.
The fourth and final reason is really just a restating of the second one.
I hope this post was of some help to you - it took 2 hours and 2100 words, so it had better be

- and I look forward to further installments.