What can i say about alien shooter? Its amazing.
Zombie shooter is an overhead action/shooter/rpg?? game that delivers nicely.
An alien treath has arrived to earth and is decimating the population. Your mission is to find how did they arrived and to destroy them. Could say more, but thats about right for the story (and i wouldnt like to give spoilers).
Anyways, a description of some aspects of the game.
Variety of enemies. Unlike many "Horde" games, this one has quite a decent number of enemies. The combination of the different classes of the enemies in the screen makes the game actually decently hard. Not to mention, i have never seen a game with so many enemies at the same time.
Good amount of weapons, most do well, some are specialized in certain situations only, but there are few that are all round up. Still, plenty to satisfy your gamestyle.
At the beginning of the game, you have a "special trait" that you can choose, which ranges from being able to recover some health x second to have some extra perception (for being able to find secrets), among others. Although you can clear the game with any, changing from one to another may affect how you progress in the game drastically according to your style of gameplay. Choose wisely.
You can use some vehicles. Not many, but its fun to squash aliens with a tank, not to mention that they would kill you in matter of secons if you are not inside.
Secret areas. To aditionally keep you busy, the game has many secret areas, most are just an extra room with some money/weapons, but you do feel rewarded, since its a decent extra loot for finding it. i found a lot, but way too far from finding every single one for every single level.
I finished this game a long time ago, i dont remember how many missions does it has (around 30), but the time to complete the game is around 7-8 hours since most missions are short, however, if you are looking every secret, killing most monsters, etc, ill be a lil bit longer. Also, the end missions are harder, and i mean it, sometimes takes longer to complete those ones (since you have only 3 lives) if going carefully.
Replay value: This game is very fun, but the amount of enemies is overwhelming, that i can become tedious at times (so basically, at the end of the game you should have slayed a couple of MILLIONS of enemies) so yeah, virtually the grey floor is red at the end of the mission. Each time you play it, you can go for different characters/stats/passive trait, but at the end, you will do about the same build, the replay value relays on killing the alien horde over and over and over again. (This is my first run with this game @Steam, but i have finished it lile 10 times or so)
Graphics. The game is not new, it has some 5~7 years under the belt, and still look nice. but seriously graphics is not really an issue, my graphics card (ati radeon 3870 at the time.) was having some trouble at the final stage due to the amount of enemies at the same time. medium graphics are OK for this game.
Sound. Not a masterpiece for sure, but it does the job, sets the mood in the game, you forget about it.
It has a co-op survival and probably a versus mode i think, Shame that no one is online ever, it might be fun to have a partner.
Survival is fun but alone feels like meh. Its quite challenging though.
Dumb AI. Although they will always try to get you, some will stuck in corners or any object that is in between, some will stuck with other aliens. However, not a great deal, since there are many enemies, being stuck they will not overwhelm you from all sides every single time, you can create some bottlenecks.
Not my intention to write a wall of text, but just to give you a general idea for your money. (probably worth 15~ bucks )