Not sure if I can post extra credits, after the submission so I will post it first here.
Credits were included in .txt files inside the .pck but I believe that I must mention them here too.
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Panoram Image (Our galaxy!) by
eso0932a.jpg
Credit: ESO/S. Brunier
link : https://www.eso.org/public/images/eso0932a/
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gruntsound.wav
aurthor : n3b
https://opengameart.org/content/grunt
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laser7.wav
aurthor : dklon
https://opengameart.org/content/laser-fire
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Zombie_Attack_Sound.wav
https://opengameart.org/content/zombie-attack-sound
https://www.youtube.com/channel/UCNHxSoU5Fon8_oZ70azzhtg?view_as=subscriber
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Zombie_Sound_2.wav
https://opengameart.org/content/zombie-sound-2
https://www.youtube.com/channel/UCNHxSoU5Fon8_oZ70azzhtg?view_as=subscriber
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Zombie_Sound.wav
https://opengameart.org/content/zombie-sound
https://www.youtube.com/channel/UCNHxSoU5Fon8_oZ70azzhtg?view_as=subscriber
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Coin.wav Explosion.wav Hit.wav Powerup.wav Select.wav Shoot.wav
Aurthor : ZigWin
https://opengameart.org/content/game-sound-effects