Bottom Line: Thirty years of accumulated design obsession, wrapped in an interface that will fight you the entire way. ADOM is one of the deepest RPGs ever built, and it does not care whether you're having a good time.
The Gameplay Loop
There isn't one. Not in the modern sense, anyway, and that's the point worth understanding before you spend money.
Contemporary roguelikes are built around a tight, legible loop: enter run, acquire build, die, unlock something, repeat. The loop is the product. ADOM's loop is closer to a campaign — you're managing a single character across an entire world map, a dozen quest lines, towns you return to, dungeons that persist, and a corruption clock ticking in the background that gives the whole thing a slow-burn dread most games in the genre never attempt.
That corruption clock is the best mechanic in the game and deserves a hard look. Chaos grants power. Chaos also mutates you — permanently, visibly, cumulatively. You grow extra limbs, lose senses, become something that can't wear its own armor anymore. The mechanical consequence is that ADOM's difficulty curve runs in two directions at once: you get stronger, and you get worse, and the skill of the game is arbitraging that gap. Most RPGs give you a power fantasy with a resource cost. ADOM gives you a power fantasy with an identity cost. Thirty years on, almost nobody has matched it.
The systems density is real and not padding. Alchemy, crafting, religion, sacrifice, skill training — these connect. Your god's disposition is a survivability resource. Your survivability determines your corruption tolerance. Your corruption tolerance determines which power spikes you can accept. Pull one thread and three others move. That's the mark of a designer who's had thirty years to sand down the seams between subsystems, and it's why the game still holds up against titles with a hundred times its budget.
Onboarding Friction Is the Central Problem
Now the bad news, and it's substantial.
ADOM is opaque by design and hostile by accident. Player reviews converge hard on this: the learning curve is brutal, the game leans on unmarked traps and unsignposted ambushes to kill characters you've invested ten hours in, and the practical solution the community has arrived at is read the wiki. Not "read the wiki for optimization." Read the wiki to know that a specific room type will end you.
There's a defensible version of this argument — discovery through death is a genre tradition going back to Rogue itself, and permadeath means nothing if the world is fully legible. But there's a difference between a game that withholds information and a game that punishes you for not having consulted an external document. ADOM lands on the wrong side of that line more often than it should. When the optimal play pattern involves a second monitor, the design has outsourced part of itself.
The interface compounds it. Dozens of keyboard shortcuts, layered menus, and an information architecture that assumes you already know where things live. The Steam release modernized the UI meaningfully — newcomers do say so — but modernizing a 1994 interface gets you a well-organized 1994 interface. The command vocabulary is still enormous. The first three hours are less "learning a game" than "learning a text editor."
Who This Actually Rewards
Push past that wall and the payoff is genuinely rare. The reason 86% of reviewers land positive despite airing every one of these complaints is that nothing else offers this much game. The variety of races, classes, skills, items, and quests isn't a bullet point — it's the reason a character build in hour forty still feels like it's revealing new options. The Chaos plot gives runs a destination rather than a score. Multiple endings mean the finish line isn't binary.
And Biskup's update policy — buy once, free updates, forever — is the kind of thing that's become quietly radical. There's no season pass. No cosmetic store. The game you buy is the whole game, and it's been getting bigger for three decades. The tradeoff, which reviewers also flag honestly, is that updates arrive on geological timescales. Long silences between patches are the cost of a one-person-driven passion project. Occasional bugs persist longer than they would in a studio product.