beautiful art, using a flinging mechanic would definitely make this game feel more fluid... as of atm, while good, ur game does feel a bit stiff, and jumps feel floaty.
when implementing flinging mechanic, make sure to use 2d golf games as a reference, you would need to adjust your levels though... maybe fling strength dictates amount of slime u lose? instead of a constant amount. anyways goodluck and dont forget to add game juice (screenshakes, sfx, camera pans, etc)
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