Tip: When determining a time limit, remember that players won't be as familiar with the level as you are. If you normally complete the level with the timer around 100, others might run out of time on their first try.
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Details for Vertical Boo Stream, horizontal wave movement
SMW Sprites - Vertical Boo Stream, horizontal wave movement
It's a Boo Steam that moves up/down with Left/Right Wave motion.
On Extra Bit Set it'll initially start moving right, otherwise it initially moves left.
It also uses first property byte for custom intitial Y speed (By default, it "Faces" Mario). More info in ASM.
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