Origin8 advance its Tower Defense franchise into must-have “territory” in this gorgeous sequel.

Sentinel 2: Earth Defense ($2.99)
It’s war, and this time it’s too close to home. The Martian mission may be over, but the aliens haven’t finished playing space invaders yet. Extraterrestrial eyes have turned to a new target: they want Earth, and you’re the one that has to say ‘no’. Welcome to the future of Tower Defense.
My Take
Ok, as James knows, this is my third TD game to review and only the third I’ve ever played. Although I do like the other two, this one is really sharp! With OpenFeint integrated (yes I am still getting used to the social networking, and it will take some time to fine tune any new system) adding some support and recordings of other games, Twitter and Facebook implied. After all the App Store is only a year old, there’s so much in front of us as gamers and the developers are hard at it. Sentinel 2 is a serious step up in the right direction from the first chapter (heck for 99 cents, go get it if you haven’t downloaded the app yet!)

Presentation
Man, it’s sooo good looking. Much better than the first installment, super clean, easy to navigate through. Even while in battle, it’s easy to rifle through your arsenal as you plan your attack or modify the defense. The graphics are good, not too PlayStation-era polygon stuff, it’s all pre-rendered and on detailed playfields. A game that looks this good would usually sell for 5 or 6.99. It’s shocking to see such a low price tag for this game.

Tower Defense Three Way Cross Examination
I’m making something out of nothing I’m sure. But there are drastic differences between the three titles I’ve played outside of themes. I’m talking about how it plays and your interaction. Defender Chronicles is a linear TD, with all the LOTR-RPG elements, is one that will beat you up good. Star Defense is also linear, but on a sphere, but for some reason easier to play, but the waves overlap. Sentinel 2, the enemies come from different parts, and not on the same line, but there are more options and tactics to use. In DC there is only one gate to protect and a certain number of foes can pass by without losing the game. SD, there’s only 10 hits on one door and it’s lights out. Sentinel 2 has several gates to protect, and many more waves from the very start of campaign mode.

Game Play
Object for Sentinel 2 is to protect the earth from a massive alien invasion, touch and drag gunners, bombers and so on to strategic locations to fend off the onslaught. Earn more money, buy upgrades to face tougher enemies as they continue to march in wave after wave. So you say, it’s the same as other TD apps? Well, there’s another layer of defense underneath the gunners, such as mobile attack drones you can buy for a price to get you out of a bind. Don’t forget the Sentinel missile attack that charges up after a few waves, very handy against the boss waves with the monsters that just won’t die.
Good news for casual gamers, auto-save is implied if interruptions occur. Just tap resume and you are back into the saddle. Proof of this, I was in the middle of a wave, I press the home button to check my email. Relaunched the app, and I was back where I left off. I think auto-save should be mandatory in all games, it’s a must for us that don’t have time to sit and play a game for hours, when we have just minutes some days.

Lastly, Sentinel 2 utilizes the OpenFeint social network to record your high scores, between friends and other apps that use the same network on your device. It’s a nice touch, but as I mentioned, all these internal social networks are in their early stages. I still think the best is yet to come with updates to follow. There’s always room for improvement.

The Cons
This is a near perfect game. I have one complaint to bring to the table, I think the tutorial needs to be dumbed down a bit or fine tuned a tad more. I sound like I’m not getting the game, but there is so many variables in the game, it does make it a little tough to dive in. While that’s a minor detail to the game, I have seen developers link YouTube tutorials to their app explaining the mechanics in depth. Very helpful in minimizing the learning curve in the beginning. Not to take away from the game, it’s a solid app, there’s so much to cover!
Conclusion
The best value so far is Sentinel 2 for your money. It’s a no-brainier to pay 2.99 for the game now, there’s no need for lite version or to wait for a sale. It’s totally worth the impulse to buy this and know it was a good purchase. Tower Defense games are getting better on the iPhone, Sentinel 2: Earth Defense is proof in the pudding. I wonder what the third installment brings us? Can Origin8 improve this gem? I think so and will keep my eyes peeled for more gaming in the future.
Related posts:

![The Red Star iPhone: Yes The PS2 Game, XS Games [GDC 2010]](http://theappera.com/wp-content/uploads/2010/03/the-red-star-iphone-gdc-3.jpg)
![Zombie Infection: New Screens And Info As Promised [GDC 2010]](http://theappera.com/wp-content/uploads/2010/03/zombie-infection-gdc-1.png)
![Mole - Quest For Terracore Gem FREE For [GDC 2010]](http://theappera.com/wp-content/uploads/2010/03/mole-gdc.png)










