I know it's too late now, but if have made this game for a jam, I would have cheat at bit and not rotated the platform with the towers and mobs, but instead I would have rotated the camera together whit the outer platform and the background. This could have been made so it looked the same way, and you would not have had issue with the objects on the rotating platform.
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Ya I thought about doing it via camera only then yes the objects would of been static. I just kind of liked the effect of the table flipping and using vinterps and relative locations to fake mob movement was something I had never done before. I always like to pick a mechanic I have never tried to create when I jam so its always a win for me skill wise, plus interesting and fun. I made the uproject public if you want the files feel free to check it out was a fun jam game.