Expansion for the turn-based tactics game
XCOM®: Enemy Within is a standalone expansion for the XCOM®: Enemy Unknown video game. It is a tactical mission-based game, and this expansion mod adds new story elements, weapons, enemy types, soldier abilities, and more. However, the core story and gameplay mechanics are largely left intact.
In terms of how the expansion pack is implemented and the way it retains the core gameplay loop, XCOM®: Enemy Within has drawn comparisons with the add-on packs associated with the Civilization gaming series.
Tactical sci-fi combat
At its core, XCOM®: Enemy Within is a turn-based, tactical combat game. The player must control an elite paramilitary organization during an alien invasion of the planet. The game is divided into different missions, and action is controlled from a 3D top-down perspective.
Enemy placement is randomly generated, and enemy positions are obscured until the player-controlled characters are within range and have a line of sight. The expansion introduces many new weapon types. While alien effectiveness has been improved across the board, and two new enemy unit types have been added, some occasional AI and line-of-sight problems carry over from the main game.
Greatly expanded content
As the expansion retains the original's core gameplay and adds new content, it makes sense to simply begin with XCOM®: Enemy Within. Playing XCOM®: Enemy Unknown without the Enemy Within expansion is only really useful to see what the game was like at release.
The standalone expansion includes XCOM®: Enemy Unknown, so there is no need to acquire that game separately. Nevertheless, so much content is added that it almost serves as both an expansion and a sequel.
An essential expansion
With new story elements, soldier abilities, weapons, resources, enemies, and a boost to enemy effectiveness, XCOM®: Enemy Within is the definitive way to experience the tactical sci-fi game and feels like an essential expansion.
