Endless Sky is a free and open-source 2D space trading and combat simulation game, created by Michael Zahniser and first released in 2015. Written in C++ with OpenGL rendering, it is inspired by the classic Escape Velocity series. You start as the captain of a tiny starship and are free to trade goods, carry passengers, run missions, hunt pirates, or take sides in a civil war — and eventually leave human space behind to discover alien civilizations.

Key Features

• Open-world sandbox — explore a galaxy of two hundred-plus star systems connected by hyperspace links, at your own pace
• Trading & economy — buy cheap commodities in poorer systems and sell them for profit, or earn income moving cargo and passengers between worlds
• Ships & fleet building — around 70 human ship models to buy and fly, each upgradeable with weapons, engines, generators, shields and other outfits
• Real-time combat — top-down dogfights with missiles, escorts and reactive AI vessels that dodge, flee and fight back
• Story and missions — one major human campaign plus many shorter mission chains and an ongoing alien storyline
• Moddable and extendable — ships, factions, campaigns and maps are data-driven, so creating and installing new content is straightforward
• Cross-platform — runs on Windows, macOS and Linux, with official downloads plus Steam, GOG and Flathub releases

Why Use Endless Sky?

Endless Sky is completely free with no paywalls, ads or in-app purchases — even the Steam and GOG builds are free to download. It is one of the best-maintained open-source spiritual successors to the Escape Velocity games, with over 300 contributors and a large, active community that keeps adding ships, storylines and alien species. If you want a deep, peaceful-and-combat space sandbox you can play offline at your own speed, Endless Sky is a polished place to start.

Use Cases

• Single-player space exploration and trading without any DRM, account or internet requirement
• Fans of Escape Velocity, Elite or Star Control looking for a free modern take on the genre
• Experiencing a story-driven campaign where your choices and combat reputation shape the galaxy
• Creating your own plugins — new species, campaigns, ships and map additions

Platform

Windows · macOS · Linux

Licence

GPL-3.0

Website

endless-sky.github.io

Similar Open-Source Games

If you enjoy commanding fleets and sci-fi warfare, try Warzone 2100 — another free and open-source strategy game.