Simulation

CorsixTH

Open source clone of Theme Hospital

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Endless Sky

Space exploration and combat game

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FlightGear

A free and highly sophisticated flight simulator

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Julius

Julius is an open source re-implementation of Caesar III

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Minetest

Multiplayer infinite-world block sandbox game

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OpenRCT2

A construction and management simulation video game that simulates amusement park management

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OpenTTD

A highly detailed transport simulation game

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Powder Toy

Physics sandbox game

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Search and Rescue II

Rescue Helicopter Simulator

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Taigo

Taigo is a virtual pet for your desktop

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Voxelands

The Fun-Focused Free Software Voxel World Game

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