Turn-based games have a thin line to walk in order to keep players engaged. XCOM: Enemy Unknown pulls players in so many different directions with both threats and opportunities t﻿hat making the tough choices it demands is as difficult as stepping away from the nail-biting situation onscreen. Defending against XCOM’s mysterious alien invasion is one of the most challenging, intense gaming experiences of this generation.

Preventing Earth from succumbing to invading extraterrestrials takes place in two phases. In the strategic view, you must manage limited time, money, and material resources to outfit your soldiers with up-to-date equipment, expand satellite coverage across the globe to keep civilian panic levels under control, invest in XCOM’s underground infrastructure, and extract whatever secrets you can from captured alien artifacts. This layer is more of an interstitial break between the randomly generated tactical missions, where the true heart of the game lies.

Firaxis’ outstanding design strips away every last vestige of tedium from combat while maintaining the agency that makes the original such a classic. Though each soldier’s actions are constrained to a basic list, the tactical possibilities are as broad as your imagination: Park a sniper up on a roof and bait the enemy into his killzone, set up behind heavy cover and breach a wall with a rocket, or occupy the enemy with suppression from cover while flanking with a second team.

Implementing these strategies is fast and easy thanks to XCOM’s clear, uncomplicated interface. More importantly, the tactics that work make sense on an intuitive level rather than being a function of learning internal math. As I got better at the game, it wasn’t because I learned how many tiles a sniper rifle needs between shooter and target to negate its close-range aim penalty. I became a better commander because I learned when to retreat instead of pressing the attack, the value of covering a reloading soldier, and to fire off limited-use abilities whenever they might grant an advantage.

The AI understands these tactical truths as well. I was pleasantly surprised to notice no bad moves on the aliens’ parts except for those easily explained by the enemies not knowing my troops’ locations. They have to scout your positions just like you have to find them, which you can and should use to your advantage.

Toward the end of the 20 or so hours a playthrough takes, you engage the aliens on more even terms with plasma rifles and psionic powers of your own. With the exception of the lackluster final mission, XCOM maintains its difficulty throughout. More and tougher aliens appear, terror missions push you out of your tactical box by forcing you to save civilians, and a few setpiece missions at certain points in the narrative present unique challenges. Even with a demigod of a sniper who guns down two enemies per turn from across the map and mind controls anything that dares to get close, a single sloppy turn is all that stands between success and failure. Nobody is ever truly safe in XCOM.

As much as I appreciate XCOM’s outstanding balance and tight design, the game could benefit from more variety across the board, and not just because I saw maps repeat (albeit with different spawn locations) more often than I’d like. Restricting the new equipment you can research largely to guns that do more damage and armor that grants more health is disappointing. The endgame super-armors that let you fly and turn invisible break the mold, but where are the flamethrowers, the flashbangs, the incendiary rockets, the crazy alien weapons that have no analog in earthly technology? Even the psionic abilities you eventually unlock within your operatives have sadly straightforward effects.

Occasional line-of-sight problems are the only blemishes on XCOM’s otherwise rock-solid technical execution. Sometimes you don’t get a shot on an alien that looks like it should be there, or run into a cover bonus when you thought you had an enemy flanked. Losing a squaddie because it looked for all the world like he could shoot an enemy (who instead turns around and splatters him) is far more frustrating than eating a death due to your own poor decisions.

The Edge

The PC version is slightly superior thanks to improved textures and resolution and drastically lower load times, but those are minor differences. XCOM plays equally well with mouse/keyboard and gamepad, and features identical content across all three platforms, so grab it for whichever system you prefer.

Multiplayer is a barebones deathmatch mode where two players beat up on each other with squads of soldiers and/or aliens customized up to a set point value. The first turn of contact tends to determine the victor given combat’s extreme lethality. Only a handful of maps are available, and there’s no persistence or ranking structure. I don’t see any appeal to the multiplayer other than playing a couple rounds with a buddy just to see what commanding mutons and chryssalids is like.

Both of XCOM’s layers present life-or-death conundrums to which there is no right answer. No matter what you pick, something or someone is going to suffer for it. This kind of tension and terror rarely occurs within mainstream gaming, and almost never with this level of skill in the execution. Don’t let the “turn-based strategy” moniker scare you off; XCOM is a singular achievement that every gamer deserves to experience.