In 1980, a group of computer-science students at the University of California started working together on a game called Rogue. Before Rogue, computer games were text-based; Rogue was one of the first to feature graphics, which it drew using artfully arranged letters, numbers, and punctuation. In Rogue, your job was to explore a vast dungeon, find a MacGuffin called the Amulet of Yendor—“Yendor” was the name of the game’s protagonist, Rodney, spelled backwards—and then make your way back to the surface, all while moving, one step at a time, as in a board game. Besides the graphics, two things distinguished Rogue and insured its immortality. The first was that its dungeons were generated on the fly, by the computer: each time you played, they were different. The second was that you had only one life: if you died, you had to start over. That uncompromising setup leant the game a tragic air. In general, video games are about defying the rules of everyday life. Rogue, despite its fantastical premise, seemed to reify them. No matter how much you explored, every game ended the same way.

Rogue’s developers couldn’t have foreseen it, but their game spawned a whole genre. Today, more than thirty years later, many games are known as “roguelikes.” Not all roguelikes take place in dungeons: Shattered Planet, a very good roguelike by Kitfox Games, is set in space. But all roguelikes share Rogue’s DNA, combining a randomly generated world with the iron rule of “permadeath.” Many also swim against the current of speed and dynamism in video games; instead, they ask you to move one step at a time. That allows you to agonize over each move—and, when the time comes, to pinpoint the single bad decision that sealed your fate.

Right now, two of the best games you can play on your iPhone (or iPad, or Android device) are roguelikes. Hoplite, by the Australian developer Douglas Cowley, emphasizes the genre’s tactical dimensions. You play as a solitary Greek soldier—apparently, he’s been separated from his phalanx—charged with descending into a lava-filled dungeon in search of the Fleece (not the Amulet!) of Yendor. Along the way, you must weave your way through hordes of tiny pixellated enemies, who assail you from all directions with swords, bombs, arrows, and magical spells. Cowley wrote a prototype version of Hoplite in a hurry, during a programming event called the Seven Day Roguelike Challenge, and the game, with its crunchy sound effects and Atari-level graphics, has a pleasantly homemade feel. And yet the game play is polished, addictive, and complex enough to demand real forethought. A short tutorial teaches the basics quickly: you can whack enemies with your shield, for example, or perform a leaping thrust with your spear. But those simple moves can be combined in surprising ways. Soon enough, you’ll be vaulting over one bad guy while pushing another into a lava flow, and the board-game world of Hoplite will feel charged with movement.

Hoplite has no story to speak of; if anything, it revels in the nonsensical nature of the roguelike genre. (After you pick up the fleece, for example, you can head back to the surface through a sci-fi teleporter.) Many roguelikes, it turns out, embrace senselessness as a kind of ironic, existential comment. When the creators of the cartoon “Adventure Time,” which was recently reviewed by Emily Nussbaum, decided to make a roguelike game based on the series, they called it “Adventure Time: Explore the Dungeon Because I DON’T KNOW!”

But not all roguelikes are quite so enamored of irony; some have a more expansive sensibility. That’s the case with Out There, a beautiful, atmospheric, space-based roguelike by two French developers, Michaël Peiffert and Fibre Tigre. On the game’s Web site, they describe it as “a dark and melancholic adventure set in deep space.” A comic-book-style introduction explains that it’s the twenty-second century, a time when the human race “tries desperately to find resources beyond its exhausted planet.” Your ship, the Nomad, is on its way to Ganymede when it is somehow blown off course. The only way to get home is to explore your way back, visiting strange planets and scavenging supplies along the way.

In an interview a few weeks back, Tigre explained that Out There was based, in part, on a short story he’d written, called “Loneliness.” Playing the game, you believe it. There is no arcade element to Out There: it’s more like a choose-your-own-adventure book. As you arrive in each randomly generated solar system, you must make a series of decisions: orbit the huge gas giant, or land on the small rocky moon? Try to make contact with that big alien ship, or carry on to the next star, despite your dwindling fuel?

Almost always, your ship is falling apart, and the aliens speak incomprehensible gobbledygook. From time to time, your astronaut interrupts the flow of events with a sad reflection on our place in the cosmos. (The last time I played, he reported that he had heard a promising radio transmission, and used up valuable fuel chasing it, only to discover that it was “just an electromagnetic burst coming from a small and lost star. Hope is painful.”) At other times, he notices the grandeur of the impersonal universe, reporting on black holes—“Around me, asteroids, wrecks and entire planets drift at an amazing speed towards the huge Black God!”—neutron stars, or, once, a moon that, upon closer inspection, turned out to be a giant ball of liquid helium, a source of wonder and of fuel.

Hoplite and Out There aren’t exciting games, because they don’t work in real time, and you can take as long as you want to decide what to do next. (If you want a pulse-pounding version of Out There, take a look at FTL: Faster Than Light.) For that reason, they’re not to everyone’s taste. Still, there’s a lot to be said for their slowness. Video games can leave you feeling tense and exhausted. Roguelikes, I find, have the opposite effect. They’re oddly restful. They encourage caution and patience. And, when you die, a whole new world begins.