Minigame mod is for version 1.4/1.5. It has 1 level and the file is 457KB in size. The file name is MGAME.zip. It was released on October 27, 2008. It requires the eduke32 port to run. Note: according to the text you just need to click on MINIGAME.bat to play this mod. That did not work for me so I just copied the files from the MINIGAME.zip file into the Duke folder then clicked on MINIGAME.bat and it ran fine.

Quote from the text file(typos cleaned up):
"This is just mini game for DN3D. Duration: 3 minutes. You must kill monsters and earn bonus scores.
Sometimes minigame spawn yellow bonus ball. Shoot him.
When game over, see the score board. Red number is BAD scores, grey numbers are GOOD scores.
Good luck!"

In this mod you need to shoot at the aliens as they pass in front of you. You start off with the pistol then change over to the machine gun part way through. You have unlimited ammo for both weapons. Hitting the yellow balls make them explode killing the aliens nearby it seems. Mouse aiming should be used for this mod. At the end the score board shows how many ailens were killed and how many got by you.

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