Flare is a free and open source 2D isometric action RPG whose gameplay will feel immediately familiar to anyone who has played the Diablo series: click to move, click to fight, loot whatever drops and head deeper. It is not a reimplementation of an existing game — it is an original tribute to, and exploration of, the action RPG genre, built on an engine written from scratch.

The project is split in two: the engine (a C++ / SDL2 core with a data-driven, easy-to-use modding interface) and the default game, the Empyrean Campaign, shipped alongside it. Version 1.15, released in May 2026, gave the game a full graphical overhaul: characters, map tilesets and the UI were all remade with Blender/EEVEE to look their best on 1080p–1440p displays. The same release added procedural map generation, a new procedurally generated dungeon called the Iron Labyrinth, and a new “Mastite” item rarity with randomised stat bonuses.

Because the engine and its game data are separated by design, the same engine can power entirely different games and mods, and third-party campaigns can be dropped in without touching code.

Key Features

• Diablo-style action RPG combat — real-time, isometric, single-player dungeon crawling with loot, stats and skill points.
• Separate engine and game data — a C++/SDL2 engine plus the Empyrean Campaign, so mods and total conversions are first-class citizens.
• Data-driven modding interface — items, enemies, maps and quests are defined in plain text files, making new content approachable.
• Remastered 1.15 graphics — characters, tilesets and UI re-textured for crisp rendering on 1080p to 1440p screens.
• Procedural map generation — including the Iron Labyrinth, a new randomised dungeon introduced in 1.15.
• Item rarity system — 1.15 added Mastite, a high-tier rarity with randomised stat bonuses on top of the existing tiers.
• Cross-platform — native builds for Linux, Windows and macOS, plus an Android engine build.
• Free and libre — no store, no account, no telemetry; both the code and the campaign data are freely licensed.

Why Use Flare?

It is a mature, long-running libre project — development dates back to 2010 and the code repository is still active — that scratches the Diablo itch without a launcher, an account or a price tag. The split engine/game architecture makes it unusually good for anyone who wants to study, mod or build on top of a real action RPG rather than just play one, and the 1.15 remaster means it no longer looks like a 2012 project.

Use Cases

• Play through the Empyrean Campaign solo for a classic loot-driven dungeon crawl.
• Build your own campaign, enemies and items on top of the Flare engine.
• Study a compact, working C++/SDL2 game engine as a learning project.
• Install it from your distribution’s repository or Flathub on Linux, or grab a self-contained build elsewhere.

Platforms

Linux · Windows · macOS · Android (engine only) · source code. Packaged for Debian/Ubuntu and available on Flathub; official downloads on GitHub, SourceForge and itch.io.

Licence

Free software: the engine is released under the GNU GPL v3 or later, and the default game data (the Empyrean Campaign) under GPL v3 and CC-BY-SA 3.0, later versions permitted.

Website

flarerpg.org · source code

Similar in the directory

• Crossfire — open source 2D multiplayer action RPG with a Diablo-like real-time combat model.
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