XCOM: Enemy Within

An expansion to the turn-based strategy game XCOM: Enemy Unknown, developed by Firaxis Games, significantly enhancing the base game with new mechanics, enemies, soldier classes, and resources. The primary addition is the alien substance "Meld," allowing players to genetically modify soldiers or transform them into heavily armed MEC troopers. The enemy organization EXALT introduces an internal conflict element, making strategic management more challenging. The expansion also includes new maps, missions, weapons, and technologies. XCOM: Enemy Within retains the tactical depth of the original while providing greater variety and experimentation opportunities. The expansion was released on Windows, macOS, PlayStation 3, Xbox 360, and as a standalone version for iOS and Android.