Move in any direction to block.Certain moves cannot be blocked (usually heavy attacks or something else that's slow)You can not block mid-air.Blocking makes follow-ups miss for a small amount of time.
You can't block moves with high knockback, that's why most heavies are unblockable.
"High Knockback"Also, Mario C.Mu n b l o c k a b l e
That counts as a low, so it's unblockable anyway
There's low block?
nope
ooh noo