Alien Rage is a mercilessly brutal game filled with fast-paced action and constant death. A non-player character sums it up perfectly when he advises the protagonist to "either own or be owned." If you are looking for a challenge, then Alien Rage will satisfy you briefly. But after the adrenaline rush subsides, there is little incentive to push forward.
Alien Rage's Steam Store page advertises it as "a truly intense, old-school styled shooter game," but that is not exactly the case. While it is certainly intense and mercifully free of quick-time events, it is more of a run-of-the-mill modern shooter. For example, the levels are linear battles through an asteroid mining facility and alien mothership; there is a checkpoint save system; you can carry only two weapons at a time (in addition to a pistol that never runs out of ammo); health regenerates; there are sequences where you have to mow down multitudes of aliens with a stationary minigun; and strategic use of cover and precision aiming through gun sights are often essential for victory. If you have played a first-person shooter made in the last 10 years, then you have already experienced most of what Alien Rage has to offer.
The main thing that differentiates Alien Rage from the next "one man must obliterate an enemy army single-handedly" FPS is its difficulty. The level of challenge provides fleeting moments of pure adrenaline, and though Alien Rage is often extremely taxing, it feels fair. For example, the checkpoint save system is generous, and enemies aren't crack shots who can shrug off a barrage of bullets. However, they can lob grenades just like you and always have plenty of buddies teleporting into the fray.
A typical minute in this fast-paced game involves sprinting behind cover to get out of range of an enemy minigun, using your weapon's sights to remove an overgrown Jawa's head, and bashing another alien to death before a grenade explodes in your face. Alien Rage has the uncanny ability to bring you to the verge of quitting before you complete a section or conquer a boss. There is a fleeting sense of accomplishment, or at least relief, that accompanies such victories.
You've seen these weapons before, and you've shot these enemies before.
The other thing that differentiates Alien Rage from countless other sci-fi shooters is its score system. Besides giving you bragging rights, your score unlocks perks that grant bonuses to gameplay elements such as your maximum health or the damage of certain weapons. You can change your perks on the fly. So if you wander into a room full of exploding barrels, you can exchange one of your three active perks for resistance to explosive damage. Your score is based on many factors, but getting kill streaks sends it into the stratosphere. Kill streaks are earned by racking up at least five kills of the same type in a row. Constantly crushing alien skulls earns you a high score, but you get even more points by executing a variety of kill streaks in the same level. Thus, you have an incentive to diversify your tactics.
For example, you get streaks for killing aliens with the pistol, explosions, headshots, and your weapons' secondary fire mode (secondary fire ammo is a limited resource shared between all weapons and replenished by power-ups). You can get multiple kill streaks at the same time by shooting five aliens in the head with your pistol's secondary fire mode (which counts for pistol, secondary fire, and headshot streaks). You can always replay a level to try to increase your score, which is the only incentive to do so, unless you want to find all the audio logs that explain why humans and aliens couldn't share the universe's most efficient source of fuel.
Usually, multiplayer modes give you a reason to continue playing an FPS, but Alien Rage doesn't offer much in that regard. Multiplayer is limited to deathmatch and team deathmatch modes and has only a few maps and a handful of servers. For what it's worth, the action is fast-paced, and the maps are well designed for a balanced multiplayer experience. Alas, that doesn't make up for the dearth of content and the lack of people to play with.
The main problem with Alien Rage is how generic it is. You've seen these weapons before, and you've shot these enemies before. You fight a lot of aliens with cloaking capabilities, minigun-toting aliens in heavy armor, aliens that explode on death, spider bots, and turrets. Additionally, most missions are forgettable, linear forays through the repetitive asteroid mining facility and alien mothership. The only notable exception is the mission where you don a mech suit and crush aliens under your feet.
The boss fights, which generally take place within an enclosed arena, are as uninteresting as most missions. It doesn't help that the bosses generally look like giant humanoid aliens wearing more armor than a heavy tank. Unless you remember them for the frustrating hour-long struggle you went through to defeat them, you'll probably have forgotten most of these bosses shortly after the next level begins. You'll have no problem figuring out how to kill a given boss, but the execution can be extremely difficult. For instance, one of the hardest bosses, the robot at the end of the mech stage, can kill you in two hits, and you have little room to maneuver when trying to dodge his attacks.
Ultimately, Alien Rage is a hard game to recommend. In spite of its sense of speed and unrelenting challenge, its monotonous level design and lackluster atmosphere grow tiring, and few people are taking advantage of the barebones multiplayer modes. Admittedly, it provides quite a rush at times, and beating it on hard or brutal feels like a major accomplishment. Yet, such feelings are fleeting. You'll be as quick to forget Alien rage as a UFO abductee is quick to forget details of extraterrestrial probing.