
Gamespy:
I consider the 1994 turn-based tactical masterpiece X-COM: UFO Defense to be the single best videogame ever made. Compared directly to that impossibly high standard, Firaxis' 2012 remake, XCOM: Enemy Unknown, does remarkably well. It's a somewhat-simplified version that nevertheless succeeds, particularly on Classic difficulty, in recreating the original's skin-tingling atmosphere, white-knuckle tension, and bottomless tactical depth. Turning the tide against alien invaders with a group of outgunned and outnumbered soldiers who live and die (and many will die) based on how our decisions interact with a virtual roll of the dice creates countless moments of sky-high triumph and staggering defeats.

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XCOM: Enemy Unknown rebooted the series back in 2012, and has since inspired numerous new strategy game series to be born.
If someone gets into this I'd recommend getting the enemy within version. It's got all the dlc included so it's the better version. Wish the author would've atleast mentioned it. I didn't see it.
Fantastic game though. Xcom 2 is top notch also. I've spent countless hours in these games.

There are few things more gratifying in gaming than skillfully turning the tide of a conflict. And few genres provide as many opportunities to abruptly reverse the odds via skill and forethought as tactical strategy. To be sure, we are more often than not talking about turn-based tactical mobile games, specifically titles in line with the iconic landmark series (XCOM and Jagged Alliance) that made the genre a genre.