The following playthrough strategy is designed to be the quickest way to unlock all achievements while minimising restart/reload times. While the game itself can be challenging and take several attempts before you find a strategy that works for you, the majority of the achievements are relatively simple and will unlock with little effort as you progress through the story.
The campaign will take an average 20 hours to complete and will require a minimum of 5 playthroughs to earn all achievements. The game consists of story driven campaign missions with random events and alien invasions happening throughout, and multiplayer that allows you to take on a friend with teams comprising of both human and alien squad members. After Earth is invaded by unknown alien hostiles, you are given command of the XCOM initiative to try and uncover the invasion plot and drive them out. XCOM – Enemy Unknown is a turn based strategy reimagining of the classic game, XCOM UFO defense. The main ones are 'Aint No Cavalry Comin,' 'Edison,' 'All Employees Must Wash Hands,' 'Hunter/Killer,' & 'Skunkworks' + Missable achievements: Several (There is no chapter/mission select so many achievements can be missed. + Cheats affect achievements: Yes, disables achievements + Minimum playthroughs needed: 5 playthroughs
