A meteor smash is when a character uses their down air, off the stage and KO's their opponent in the process. Useful technique used in competitive battling.
The notable Meteor Smash is obviously Mario's, but there are many other methods that other characters utilize to dunk their opponents.
Not all Meteor Smashes are utilized as an A-Button attack. Some special attacks, like Donkey Kong's Headbutt and Captain Falcon's Raptor Boost (when used mid-air), have a Meteor Smash effect when used.
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