Sentinel in Review – TD goes Sci-Fi!

One of the things I love about the app store is the sheer amount of choice.  Don’t get me wrong, some days I hate it as well also for that very same reason.  But, when you like a specific genre, such as TD games for example, it’s a nice place to be able to visit. Sentinel, by Origin8 is the latest addition to the TD bunch.  I won’t go into explaining TD games as it has already been done here at Touchmyapps in several reviews, but Sentinel brings in an element of science fiction and nice looking graphics which does add a fresh vibe.


“You are commander of the dropship Sentinel. You must defend a distant colony from the alien hordes in this stunning new evolution of tower defense.

Protect key structures which block the enemies’ path as the aliens smash their way towards your stronghold. Utilize an array of advanced technology including upgradeable towers and droids which can repair buildings or harvest resources.”

Sentinel offers you 2 play modes, Assault and Endurance, though Endurance is locked until you have completed the level.  There are 4 difficulty choices ranging from easy to psycho.  And there are 3 maps to play through, with only the first also being unlocked when you startthe game.


First thing you will notice (or at least first thing I noticed) was the pretty graphics.  The levels are highly polished, and you can zoom in and out for greater detail without any lag.  The animations are also very nicely done.  Aesthetically, this game is very nice to look at.

Second thing I noticed was the sound.  For a TD game, the sounds are great.  The intro music was fantastic, the explosions and lasers all make nice sounds which help set the atmosphere.

Probably what I liked best about this game, is the addition of the repair droids, “interest”, and bonuses for keeping your barrier/dam structure standing.  Repair droids (when you have enough money to purchase them) are able to repair (obviously) your structures, but also will go searching for resources, which in turn provide more money.  It’s a nice little change in strategy.  “Interest” is another aspect I found that was significantly altering my game play.  At the end of each wave, you receive “interest” in terms of bonus money for not using all your money and rationing the use of towers.  You are constantly debating between adding towers or playing a little game of risk, hoping to get more bonus money.  In a game that offers online global leaderboards, this brings some added replay value.


The final other ‘twist’ to Sentinel, is the use of barriers/dams.  This essentially cuts the board/maze into smaller sections (until your barrier is destroyed of course).  You need to strategically think if you want to guard your structure and accumulate bonus points after each wave, or build your towers for the entire board.  Again, this adds more strategy in terms of how you want to complete the board and where you want to end up on those global leaderboards.


You do need to be aware that there are only 3 levels/boards.  Your first level has 60 waves, second level has 90 waves, and the third level has a whopping 120 waves.  I don’t necessarily have an issue with only having 3 boards as I’ve already mentioned the different use of strategy that can be used (though don’t get me wrong, more levels are always appreciated).  My issue is more with the pacing of the game.  I couldn’t help but feel it was a little slow at times.  It’s likely to do with the amount of time between each wave.  Once you complete a wave, the time before the next wave starts is just a touch too long, and there does not seem to be a way to skip it.  You get notified of your score, your “interest” and it just takes a little too long, which kind of takes you out of the game.

My other comment is in regards to the lack of visual change when upgrading your towers.  There really doesn’t seem to be a lot to visually see that your tower has been upgraded.  In fact, the beam and laser when upgraded don’t appear to have any difference in what they are shooting.  It would be nice to see a different animation for those weapons.  They are extremely expensive in the game and I like to see the upgrade.  It makes me feel better…

sentinel5Don’t get me wrong, I like the new addition to the TD family.  I personally don’t think we can have enough TD games (talk to me after I’ve reviewed 50, I may reconsider).  I very much appreciate a new science fiction theme, and the graphics are extremely well done.  Each TD game has their own little nuances, and if you like TD games, there is enough that makes Sentinel fresh and worth your time.

Update: Origin8 has heard your (and ours) feedback regarding the pace of the game between enemy waves. You should be happy to know that a fast forward button has already been implemented and will be included in the upcoming lite version of Sentinel as well as the full game. And of course, more maps and enemies are also in the works.  Nice!


App Summary
Title: Sentinel (v1.0) Developer: Origin8
Price: $4.99 App Size: 8.4 mb
  • Excellent Graphics
  • Great Sound
  • New Strategy Elements
  • A little slow between levels
  • No noticeable change for upgraded towers
  • Only 3 levels


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