Counter

Counter is 's down special move in Super Smash Flash 2.

Overview
When performed, Marth poses with his sword in reverse grip, with a small, metallic "chink" sound being heard. When hit while this sound plays, Marth suddenly turns to the direction of the hit and counterattacks with a slash forward without receiving any damage from the hit, becoming invincible until the moment he slashes. The damage and knockback dealt to opponents hit depends on the damage normally dealt by the counterattacked move, with a minimum of 7% damage with weak knockback and a maximum of 20% damage with moderate knockback.

The move is effective for dealing with attacks that can be easily predicted, including many opponents' recoveries, which also makes it an excellent edgeguarding tool. Despite this, the move's relative lack of knockback does not make it a reliable KO tool. Additionally, Marth is not invincible after he counterattacks and can still be hit by certain attacks with multi-hit or lingering hitboxes, including explosions and certain projectiles.

Origin
Counter is based on a core element of  gameplay: in all games of the series, when a unit attacks another unit, the targeted unit will perform a counter-attack to strike back at their attacker if they currently have an equipped weapon with a compatible range.

Trivia

 * Counter is one of Marth's only attacks that does not have a sweet spot at the end of his blade.