actually.. since you already have a "click to continue" thing... instead of reseting the game while clicked it could set up the next level. all you would do is change the building with the robot/s. the same programming would work with your other games too, you've already done the hard part.
more levels should be simple enough, just put a timer after the robot is killed and set up the same substances. after the last level make it go to a screen for level select which will shoot you to a specific time frame of the game. This is a great start, but you have to keep pushing!
hey really nice game here... but I just wanted to point out that there is a certain way you can get across spikes. By jumping and using the lack of friction I was able to make my way across the spikes and get the diamond in one level.
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no u