I was especially watching for the sidechaining part but the kick part is awesome as well :D You learned me some things I would never have learned if it wasn't for this tutorial :D (don't know if that's correct english, but you get the point :D)
But a good version of pong! I love the achievements, that's what kept me bussy.
Ans I agree with Mikel, maybe you should make the 4 way pong a little earlier so you don't have to win 20 games before you can play it.
The grapics were ok, but maybe you can add some background to it, that would be cool.
Usually I don't really like stick shooters, but this one changed my mind, I really like the way you have to aim with the mouse and the weapons in the shop.
The only problem I see is that you don't really need the shop weapons,
you could do everything with the starting weapon, maybe make it a bit longer or make the starting weapon weaker.
But the whole game: AWESOME
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