A meteor-smash is an attack that sends the opponent downwards at high momentum. It is vital that this move not be confused with a spike, which is functionally similar but has different properties. In response to a meteor-smash, it is also possible to meteor-cancel. A character's second jump and third jump (Special recovery) are all valid ways of meteor canceling, and must be performed immediately after being hit. In Brawl, spikes do not exist, and any attack that sends you down is a meteor-smash and can thus be meteor-canceled. However, in Melee, spikes were unable to be recovered from until a character had moved a set distance. Not all characters have access to a meteor-smash.
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