Bets.

Option 2. There are not only a lack of details but also no connection between units, or any internal cohesion within the race. I understand that

the Irns were conceived as a mystery, an unknown, and therefore I didn't come up with a definition for them

But the result is a classic NOX. 7 units without any logical connections, either between each other or between upgrades. You want to go? Let's go:
1. Lizard/Deep-sea Lizard. Perhaps the most thought-out of everything you wrote. Only one question: they live in deep underground lakes, so are the Irns subterranean?
2. Bugargo.

These monsters don't obey anyone, but at the same time, for a good piece of meat, they are ready to rip anyone's throat out.

Um. Can't he just eat the enemy? And why wouldn't an enemy give him a piece of meat so he'd leave them alone or even attack his former masters? The upgrade, in your words, is "interesting for its proximity to large dragons." I'm already anticipating something big and interesting. Reading further: "This little creature" facepalm.
3. Spawn of Squarn (who is Squarn?) instead of the ancient male pastime, measures his "damage strip length" (actually, my head cannot process this; I have three different versions of what this could mean). The fanatic's blades are soaked in the poisonous blood of Garnigo, but Garnigo himself is not poisonous—you can hit him without any harm to your health; so what if some poisonous blood splashes out? How does that work?
4. Here is my favorite part.
Irn Warrior, a "hard trial for any merchant or rich man who didn't bring guards." Holy crap. It says "Elite" before them. What kind of race is this, where elite warriors can be a hard trial (not an obstacle, but a trial) only for merchants and rich men without guards? And where have you seen such merchants? Rich men are possible—look at Godric, for example; he's surely wealthy enough to travel alone. In short, facepalm again. Reading further: "strong," "has a poor physique"—explain to me, the son of an athletics master of sports, how is that possible? "Accustomed to going without armor"—well really, why do mutants need armor? To defend themselves against merchants and rich men without guards? He's probably not stupid enough to fight those with guards; better to run away, and armor won't get in the way.
He becomes a prison-dweller—maybe you meant jailer? Or is a prison-dweller someone who just lives in prison but isn't an inmate or a jailer? In general, it's only natural to end up in prison with such a lifestyle, so a prison-dweller is apparently an inmate. Reading on: "retired warrior"—well of course, you can't fight wars in prison. And yes, pardon me, but in Heroes we hire an army; what is someone who has ALREADY retired doing in it? Or will we lose units upon upgrading? "Terrifying with his battle scars, he frightens every opponent"—you see, hysteria can come not only from fear, but also from laughter; I would laugh for a long time too if I were given a face scratched up by a merchant's wife as "battle scars." "Compared to himself previously, he wears sturdy armor"—now that's correct; he didn't run away, he got into prison, so now he can put on armor.
5. Cult Lord. "The cult of worship for Squarn is very influential among the Irns, and its Lord is the closest friend of the ruler"—just how many close friends does Squarn have, huh? Classically, a level 5 has a growth of 3 per week, or 6 with a castle. I want that many friends. "Terrifies everyone, even with his outfit, reducing the enemy's initiative"—nonsense; in Heroes 3, magical elementals showed what they had under their cloaks (exhibitionists, damn them) and some enemies even died from it. "Kept a poisoned blade from his past"—what past? If he was a fanatic, why isn't this the fanatic's upgrade? Or is he also just a highwayman? And the sentence as a whole is a joy: "This warrior kept a poisoned blade from his past, but at the same time has a magic staff, thanks to which he has no penalties in close combat." Let's break down the sentence. Besides the poisoned blade, he has a magic staff; thanks to this staff, he has no penalty in melee. So does he chop with the blade from a distance? Ah! I get it! I watched Bleach; his blade is like Ichimaru Gin's—at bankai it grows to 13 km and can contain poison inside!
Shadow. "After death, the cult lord is reborn as a shadow traveling through the world created by Squarn." Explain to me how they upgrade? Are lords killed on purpose? "But the strongest among them break back into the Otherworld, where they become the strongest of the cult fanatics." The strongest break out to become the strongest. And returning to the upgrade questions: how many lords have already been killed? If only the strongest break out, then HOW DO THEY ALL UPGRADE? I'm not even mentioning that we get a lord from a fanatic—meaning he is logically stronger than a fanatic—and from a lord we get a shadow, the strongest among fanatics. Which means the same lord.
6. "Rotten Dwarves are traitors to the mountain Brotherly Empire" (since when does Bratsk have a mountain empire :eek:), "terrible sneak-//slinks, hiding in the dark corners of houses" (what if the empire finds and punishes them—scary!), "and afterwards they report to the lords." Well yes, indeed sneaks; they hide, and then the lords have to look for them so they can report.
Brother of Darkness
"The time comes and darkness swallows the rotten dwarf whole"—correct, no point sitting in dark corners for too long. "Previously he could neither run nor walk" SUDDENLY! :eek: "In battle he emits dark vapors"—meteorism? Poor guy. "Destroying everything that disagrees with his life theory"—not destroying; everyone just runs away from the stench.
7. "Assassin—a warrior of a mysterious order, terrible and powerful"—no way, first level for a dungeon. "He hides in the darkness, convinced that every murder serves the good, while in reality he is merely a weapon in the hands of darkness"—an assassin with holy naivety :smile40::smile40::smile40:. I'm crying :smile40::smile40::smile40:.
Brother of Mercy. This is already funny :D "And so the assassin realizes that he has brought much pain"—holy cow, did he think he was giving massages with his weapon before this? "and turns into a healer with strong armor and confidence in the power of light on earth." I wept. I can't write normally anymore. Sorry :smile40::smile40::smile40::smile40::smile40::smile40::smile40: "His strike is not strong, but then again, the allies of the brother of mercy can live forever." Well at least we know the allies: Elvis, Tsoi...