The biggest installment of the award winning Sentinel sci-fi tower defense series now on PC! Take the fight to the alien homeworld and unleash a massive arsenal of weaponry. Get up close and personal on the battlefield in your power armor to execute devastating attacks and support your defenses! * An epic campaign across 20 levels.
User reviews: Mostly Positive (63 reviews) - 79% of the 63 user reviews for this game are positive.
Release Date: Nov 26, 2010

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Recent updates View all (5)

June 4

Vote for Sentinel 4: Dark Star on Steam Greenlight!

Sentinel 4: Dark Star is now up for consideration on Steam Greenlight, and we need your support! Hit the link and give us a thumbs up if you'd like to see the biggest and best Sentinel game on your PC:

Sentinel 4: Dark Star on Steam Greenlight

Sentinel 4: Dark Star is built on our brand new game engine, which is much more tailored to a PC release than our older Sentinel 3 technology. We've already got the core of the game running smoothly on Windows (check out our Greenlight video and images!) so while there's still work to be done, it shouldn't take too long to bring the game to full release.

We can't do it without you, though! Please take a look, vote us up if you like what you see, and spread the word to let Valve know that you want this game.

Thanks in advance for your support, and we'll keep you up to date on the campaign's progress!

Team Origin8

1 comments Read more

June 4

Sentinel 3: Homeworld update now live!

Today we've got an update with a couple of general enhancements:

  • Added VSync which will cap the framerate to the refresh rate, thus reducing CPU load on fast machines as well as improving visual quality.
  • Added Steam achievement progress tracking for "Kill X enemies" achievements.
  • All audio is now suspended/resumed as the game window is minimised or goes out of focus.
As always, let us know in the comments or forums if you run into any problems, and enjoy!

1 comments Read more

About This Game

The biggest installment of the award winning Sentinel sci-fi tower defense series now on PC!
Take the fight to the alien homeworld and unleash a massive arsenal of weaponry. Get up close and personal on the battlefield in your power armor to execute devastating attacks and support your defenses!

* An epic campaign across 20 levels.
* A powerful commander unit which can level up and gain new abilities as you play.
* Over 20 unlockable turrets, orbital ship weapons, automated drones and abilities at your disposal.
* Customize your weapon loadout in the Armory to match the demands of the mission.
* NEW: Includes new content featuring new commander, enemies, campaign, weapons and more!
* Endless modes for all maps.
* NEW: Steam Achievements
* Classic mode allows you to compete for scores in a pure skill-based game mode.
* Exclusive music by Specimen A.

System Requirements

    • OS: Windows Windows Vista or Windows 7
    • Processor: 1.2GHz+ Processor
    • Memory: 1 GB RAM
    • Graphics: OpenGL 1.3 gfx card/driver with 128+MB Video Ram
    • Storage: 300 MB available space
Helpful customer reviews
7 of 7 people (100%) found this review helpful
128.6 hrs on record
Posted: July 31
Ok, first thing - that "recommend" is more like "take it at your own risk". Shame there is no such option. With that said - game is not exactly bad, but it has a lot of flaws. But let's start with good part - game has lots of maps (35+), lots of modes and difficulties and nice interest system where you have to keep your defences to minimal, which adds to tactical part. That's about it for the good part.

Now about bad stuff - first of all, game is really long. Each stage (except maybe very early ones) lasts at least an hour. On it's own that wouldn't be so bad, but you can't speed up the game more than 2x. Considering that some games has 3x, 5x, even 9x speed ups - very poor desicion. Next thing - in every stage to collect more money (and gain more interest money) you have to do your best to kill enemies withlou building anything. So you have to use abilities and your commander (yup, you have movable unit to help you) for a good 20-30% of the stage. Way to go for a TD, instead of tactical managing limited resourses you must jump around to collect money. Another bad thing is - there are basically only 8 types of enemies with small variations, nothing interesting really. If that was a game for 20-30 hours, it'd be ok, but game for 100h+? Definitely bad. And there is more! Towers are majorly disbalanced, by the end of the game you really need only 4-5 towers from given 12 - as if 12 was too much to make it more or less balanced. Well, that's it for big ones, i may also add couple small ones - bad graphics (but i guess if you play TD you don't care like me, still had to write about it), repetitive music (remember 100h+ of gameplay, on the other hand you can turn it down - again, like i did) and small glitch when you choose chapters, but that's not really an issue, just a bit annoying.

So. After all that you may ask why i even put "recommend" on it. Well, not everyone completes games on 100%. If you want to complete campaign and leave, i suppose, it's not so bad. I give this game 5/10, because it's badly flawed and artificially prolonged, but you may still enjoy it. Just don't go too deep.
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95 of 113 people (84%) found this review helpful
1 person found this review funny
2.3 hrs on record
Posted: February 7, 2014
First things first:


I am sorry, but it is. This is exactly the mobile game, ported to PC without changing anything. It has no resolution options (and only a low/high quality setting, nothing else). It only runs in window mode or in a stretched (!) fullscreen mode. Really, really bad. I have a native resolution of 1920*1200, so why the hell can't I get this exact resolution in the game? Instead I get this ugly, stretched mess. But ok, I can live with it. Tower defense games were never about the graphics, right? The interface is exaxtly what I know from the iphone. They really didn't change a thing. For instance, if you drag a weapon to a free slot in the armory, it becomes zoomed in in your hand/mouse cursor, which makes sense on a mobile device. It looks horrible and ridiculous on a full HD display though. And they added absolutely nothing. No achievments, no trading cards, no nothing. I really have to assume, that the developers only wanted to make a quick buck with this.

Which is really a shame, because the game itself is actually great. It is exactly what i expect from a tower defense game. Looking at all the newer TD games which try to implement more interaction (like running around with a hero), this is rather old-school. And it is exactly how i like my TD games. Searech for optimal spots for your towers. Find the right balance between getting lots of interest each round and not dying. Love it! And the commander is a nice addition to the already great gameplay of its predecessors. It gives you a little bit of additional interaction, but not too much. For me personally the commander is about as much interaction (besides placing and upgrading towers) as I can take. Perfect!

I really like this game, and that's why it gets a thumbs up. I was really struggling though, because this port is basically a punch in the face of all Sentinel fans. I would have expected more. I pay more money for this than on the iphone after all, so I think i can expect more, right? Whatever, the game is still a lot of fun. If you like traditional tower defense games, this might be the game for you.
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66 of 79 people (84%) found this review helpful
16.2 hrs on record
Posted: February 8, 2014
This was a solid tower defense game on android. The Steam version suffers from being a lazy port. The controls haven't been properly reworked for PC, the slider where you select your mission is slightly bugged (clearly intended to be swiped with a finger and just badly ported over for mouse), and the graphics are poorly detailed when viewed on a normal sized computer monitor or TV.

I think if these guys had just put in a bit more effort, it could have been a good port. As it is for now, there are better tower defense games to be played instead.
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63 of 90 people (70%) found this review helpful
1.5 hrs on record
Posted: February 3, 2014
Solid, Simple, Tower Defense for fans of the genre. This is primarily a fixed path, but flexible tower placement game. Not a maze builder.

After about 30 minutes of play, it appears to just be a bug free, direct port, of the mobile version. That is not necessarily a bad thing. I already own the android version and have beaten it before. Too many mobile to PC ports are buggy right off the start. So far this works fine for me in either full screen or windowed mode. Thumbs up to a smooth mobile to PC transition for the Devs.

It’s a good addition for fans of the genre, especially if you don’t already have it on your tablet or phone. This is best for those that prefer a more 2D tower defense where you focus on upgrades and tower placement like Onslaught, Fieldrunners, iBomber Defense, or Defender’s Quest.

If you prefer a more complex fully 3D tower defense that uses more of the PC’s gaming power I’d recommend checking out Prime World: Defenders, Dungeon Defenders, Sanctum (1 or 2), or Defense Grid.

I enjoy both the simple 2D and complex 3D Tower Defense games. So I was more than happy to add Sentinel 3 to my Steam collection.
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31 of 44 people (70%) found this review helpful
1 person found this review funny
29.3 hrs on record
Posted: August 8, 2014
I hate myself for trying to play this game, it starts out good (first hour) but then it's the same over and over again. The more difficult it gets the longer it takes to clear the stages (it actually doesnt raise the difficulty) so its always easy. It just takes forever, It's will slowly drain the life out of your soul,

2 campains / 40lvls of the same stuff, 4 difficulty settings = 160, + endless and challenge mode = i dont know 40 more / 200 levels

A level usually takes 20min on easy and up to and hour on hardest, on endless mode its infinite so if you want to beat the game, its atleast 200hours. And it's the same thing over and over again, you dont need to think or do, just sit there and watch for 200hours, sounds like fun right? well it's not!
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