bio is a spin, where youre spinning on a axis that is between standing on your feet and lying horizontal. corked is a spin, where the axis is over lying horizontal and being inverted. you can do bios whereever you wanna, backwards, sideways or you lean frontwards, like most people do. Same with corked.
It may LOOK like a off-axis rodeo or a off-axis misty, but it ISNT.
Flatspin is, i think a lincoln loop where you are lying on your back. Or a backflip where you are lying on your side. One of them.
That is the information that i got from the LINE tricktionary. On this site should be the same in the tricks section.
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