this has probably already been found but if you land on a platform with aerial up b and it goes into the ground animation it will have 2 hitboxes that combo into each other. Pointless but I thought I would share it anyways.
Edit: Heres a Gif
https://gfycat.com/PepperySophisticatedBlacklab
Edit: Heres a Gif
https://gfycat.com/PepperySophisticatedBlacklab
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