this star coin challenge is entirely based around item preservation, using a fire flower to defeat the large normal pirahna plant. this could work on it's own, but...
...(i'm invisible due to invincibility frames.) of course, you can cheese this by damage boosting. (and no, the item reserve slot isn't the problem.)
i hate challenges like these, because of this particular cheese. i would appreciate info on how to somewhat solve this, but i'm more interested in how to prevent this, as well as other star coin challenges that could work in place of what's here.

You can use a zone with sprite 168 to detect the power up the player has and bock his way to the star coin by spawning some solid tiles with tilegod if it's not the fire flower. You could also have some tiles there by default that only go away if the piranha plant is defeated, which would also be achieved with a zone, sprite 168 and the tilegod sprite. I do think it'd be better if you just let the people who want to cheese do their thing. It's not like damage boosting comes with no consequences.
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Nothing to say, so jadnjkfmnjamnfjkldnajfnjkanfjdksan jsdnvj m.