HyperRogue is a free, open-source puzzle roguelike that takes place on the hyperbolic plane — a world where geometry simply does not work the way you expect. Instead of a rectangular grid you navigate a mosaic of hexagons and heptagons in which parallel lines diverge, triangles add up to less than 180°, and you will almost certainly never return to the same place twice. You play a lone adventurer collecting treasure from around 70 distinct lands, each with its own monsters, treasures and magical Orbs, on a quest for the legendary Orbs of Yendor. Written by Zeno Rogue and still actively developed, it is one of very few games built on genuinely non-Euclidean geometry — and it teaches that geometry as you play.

Key Features

• A hyperbolic world — the playfield is rendered as a Poincaré disk of hexagons and heptagons, generated dynamically as you move. The infinite plane is packed into a finite view, so straight-looking lines diverge and space grows exponentially outward.
• Around 70 distinct lands — each land has its own theme, tiling, terrain features, native monsters, treasure type and magical Orb power. More lands unlock as you prove yourself, ending in Hell and the Orbs of Yendor.
• Chess-like, fully predictable mechanics — enemies move by fixed rules and most are killed simply by moving into them, but a single attack can kill you too. The game refuses moves that would kill you instantly (the "check" rule from chess), so losses are your own fault, not the interface’s.
• Treasure-driven difficulty — collecting treasure is what makes monsters spawn faster, so difficulty is something you dial yourself, land by land. Collect 10 treasures in a land for the basics, 25 to master it.
• High-score and achievement system — persistent scores, unlocks and challenge modes give the minimalist ruleset a long tail.
• Keyboard, mouse or touch — move with the numpad, vi keys, mouse or touchscreen; rotate the world with the arrow keys; hover for tooltips and right-click for detailed information about any object.
• Runs almost anywhere — Windows, macOS, Linux, Android and the web, from the same C++ codebase. It is a small download that runs happily on modest hardware.

Why Use It

HyperRogue is a rare thing: a game that is genuinely educational about mathematics without ever feeling like a lesson, and one whose rules fit on a postcard while the play space is effectively infinite. Because it is turn-based and has no twitch element, it suits any hardware and any pace of play; because it is GPL-licensed, ad-free and completely offline, nothing is monetised behind your back. If you like puzzles, chess-like tactics or roguelikes, it is unlike anything else in the genre — and the fixed, inspectable rules make it a good way to build intuition for hyperbolic geometry. The source is a single well-documented C++ project, so it is also a friendly target for tinkering, new lands and community contributions.

Use Cases

• Roguelike and puzzle players who want something mechanically unlike every other entry in the genre.
• Anyone curious about non-Euclidean and hyperbolic geometry — playing is a far more intuitive introduction than formulas.
• Gaming on low-spec, old or offline machines, including phones and tablets.
• Playing in short sessions: each land is a self-contained challenge with its own goals.
• Exploring and modding a mature, readable open-source C++ game with a data-driven content system.

Platforms

Windows, Linux/Unix and macOS from the official site; Android from Google Play and F-Droid; and a browser version you can play in the web without installing anything. The current free release is 13.1o (August 2026). Paid versions on Steam and itch.io include extra lands and social/competitive features, while the free version remains fully open source — source code and downloads are also published on GitHub and itch.io.

Licence

Free and open source — GNU General Public License, version 2 (GPL-2.0). The game code, data files and artwork are all open source; paid releases add content but do not restrict the licence. The featured image is a real in-game screenshot taken from the project’s official screenshot gallery.

Alternatives

• Dungeon Crawl Stone Soup — a free, open-source (GPL-2.0+) roguelike with a more conventional dungeon-crawling structure if hyperbolic geometry is a step too far.

Website

roguetemple.com/z/hyper/ — official HyperRogue site with downloads, the illustrated gallery of every land, and the browser version. Source code: github.com/zenorogue/hyperrogue.