Set in the year SE 3256, the player is thrust into mankind's first interplanetary war between the Earth Alliance and the Ares Confederation. As the promising captain of the experimental dreadnought prototype, codenamed Sierra. Your sole objective is to help turn the tides of the war, utilizing the ship's advanced combat systems, flexible energy allocation and optimized platform deployment capabilities. To the captain, the core principles of prudence, guile, resource management and patience are essential to survival. The technology incorporated in Sierra allows it to explore multiple paths to victory: evade and assault enemy ships in classic broadside warfare; research armaments and upgrades to outgun the enemy fleet; or outnumber them with remotely-controlled weapon platforms. Rout the enemy’s armada in order to quell the rebellion and save Earth from the corrupt colonials.

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2 comments by Kalus on Jan 21st, 2014

So here we present to you, the build that you've been waiting for: It is now designed to let you play the game continuously and is now a lot easier to understand how Sierra Ops is played - hopefully!

PC :
Direct Link -

Mac :
Direct Link -

Linux :
Direct Link -

Mediafire Folder:

Known issues:

  • Sometimes, you can't enter the Resupply Station. So what you should do is simply enter the LITE simulation, and escape right away, and then return to the station.
  • The free camera mode sometimes has issues with the platform mode, making it hide the mouse cursor. The solution is to just alt+tab back to the game to regain control of the mouse.
  • The Mac/Linux release hasn't been tested thoroughly, as well as Win8. Volunteers are very welcome to try the game, and report the problems to us by sending an email to
  • The pause/battle menu is just a placeholder, but the window/full screen mode button there works.

Additional Information:

  • The Harbinger cannon requires Level 20 weapon and Level 20 Particle Capacity.
  • The abilities in game uses the shortcut keys E,R,T, but you need to learn the appropriate skill for it in order for them to work.
  • We've also made the Leviathan more active and has a second mode at 30% hp and below. If you can record your battle with the Leviathan and has managed to defeat it, the first three people to upload at Youtube will win an all digital bundle! (It's the 80$ perk at our IndieGogo, containing exclusive digital works such as the game design book, HD wallpapers and Original Soundtrack - )
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Operation SD (demo)

Operation SD (demo)

Mar 28, 2012 Demo 1 comment

Press "read more" for instructions on how to play the game.

Post comment Comments  (10 - 20 of 57)
SERgius Jul 9 2013, 7:40pm says:

Hey there. I just bought this game recently after playing the demo.(worth every penny =) ) But now i got this error that i can't solve.

+2 votes     reply to comment
Kalus Creator
Kalus Jul 10 2013, 1:21am replied:

Hello, can you tell me any other details about the error you encountered? You can do this by checking the errorlog.txt file inside the Content folder where Operation : SD is installed. thanks

+1 vote   reply to comment
SERgius Jul 10 2013, 2:12pm replied:

Sure. Here is a part of it

7/9/2013 12:48:49 AM : System.IO.FileNotFoundException: Could not find the file C:\Users\Owner\Documents/Innomen Productions/Operation SD/ShipDataFile but found the directory c:/users/owner/documents/innomen productions/operation sd/ Did you type in the name of the file wrong?

+1 vote     reply to comment
Kalus Creator
Kalus Jul 10 2013, 10:54pm replied:

Go to C:\Users\Owner\Documents/Innomen Productions/Operation SD/ folder and check if the ShipDataFile is present there.

If not, go back to where Operation:SD was installed and go to Content/Databases/ folder and copy the ShipDataFile from there.

You might also want to copy the MissionDatabase.csv file from the Content/GlobalContent/ Folder if the said file is not yet present in the operation sd save directory.

Alternatively, you can run the OPSDSettings.exe (it might give an error, just press continue) and press the ResetSaveData button.

+1 vote   reply to comment
SERgius Jul 11 2013, 12:19pm replied:

Ok So The game finally running but i ran into error. The game started with half the screen showing and then it close. I check the error report and this is what i got.

System.NullReferenceException: Object reference not set to an instance of an object.

+1 vote     reply to comment
Kalus Creator
Kalus Jul 11 2013, 10:11pm replied:

That is odd. Try re-installing the game to see if it fixes things up. The error indicates it cannot load/find certain resources. Also are you installing the game from the stand alone build or the Desura build?

I also seem to have the half screen problem where the videos are supposed to play. I suspect an XNA problem seeing as we made the game on XNA 3.1 it probably didn't aged well. You can still access the tutorial videos inside the Content/Transitions folder as wmv files.

+1 vote   reply to comment
SERgius Jul 12 2013, 12:59am replied:

I got from the desura Build. and I also tryed re-installing several time, but it still having that same bug.. plus i don't seem to have that transtion folder of any sort.

+1 vote     reply to comment
Kalus Creator
Kalus Jul 12 2013, 1:20am replied:

Hmmm, if you don't see the Transitions folder inside the Content folder then something must have gone wrong with the downloading/installing process.

Also, there should be 3 files inside the Operation SD savedata folder (the one inside your documents folder) namely ShipDataFile, MissionDatabse.csv and ErrorLog.txt.

if you see all of them there and you still have an error then try downloading standalone version. I tried installing via Desura on my end and it worked out just fine so I am quite stumped at the moment on what the problem on your end is XD.

+1 vote   reply to comment
SERgius Jul 12 2013, 1:40am replied:

Uh right. where to find taht stand alone version...

+1 vote     reply to comment
Kalus Creator
Kalus Jul 12 2013, 1:53am replied:

try going to this link.

+1 vote   reply to comment
SERgius Jul 12 2013, 12:03pm replied:

Thank you. the game is finally running but the small videos still have that half a screen thing. everything else is fine.

+1 vote     reply to comment
smartysmars May 27 2013, 7:54am says:

interesting game.

+3 votes     reply to comment
Seryuu13 May 1 2013, 6:34pm says:

Hm this looks interesting i give it a tray

+3 votes     reply to comment
cybersleuth58 Nov 27 2012, 2:22pm says:

I cannot get it to run. First I get the error there is no suitable graphics card. Then it tells me it requires pixel shader and (I am blanking). Then it crashes. Any ideas?

+2 votes     reply to comment
Kalus Creator
Kalus Nov 28 2012, 7:02am replied:

Hmm, can you tell me what is your video card? This error usually happens if the video card of your current setup does not have at least pixel shader 2.0. ( A requirement of the XNA framework)

+2 votes   reply to comment
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Operation SD: Space Defense
Developer & Publisher
InnoMen Productions
Custom Built
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Release Date
Released Apr 5, 2012
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21 votes submitted.

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Highest Rated (2 agree) 10/10


2,29 € Only? + 2 12/10

Apr 10 2012, 3:21pm by stygma1982

Tactical Shooter
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