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games/strategy/open_xcom.md

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+# OpenXcom
+
+_OpenXcom is an open-source clone of the original UFO: Enemy Unknown (X-Com: UFO Defense in USA)._
+
+- Home: https://openxcom.org/
+- Media: <https://en.wikipedia.org/wiki/UFO:_Enemy_Unknown#Fan-created_content>
+- Download: https://openxcom.org/downloads-milestones/
+- State: mature
+- Keywords: TBS 
+- Code: https://github.com/SupSuper/OpenXcom/
+- Language(s): C++
+- Code license: GPL-3.0
+
+OpenXcom requires a vanilla version of the original UFO: Enemy Unknown / X-COM: UFO Defense (any edition) with the latest patch.
+
+## Building
+
+Uses CMake
+