Spike

A spike is an attack in the ' and ' series that sends enemies downwards. Unlike meteor smashes, spikes cannot be meteor cancelled, making them very powerful tools for edgeguarding.

In Super Smash Flash
Although the How to Play tutorial mentions meteor smashes, meteor cancelling is absent from Super Smash Flash. Therefore, the game only contains spikes.

Every character's can spike. Due to the instant-KO attack glitch, however, getting those moves to actually spike is considerably difficult; they will not move grounded opponents who are idling, and will strongly semi-spike opponents who are moving horizontally. In order to properly spike opponents, one needs to hit an airborne opponent who is not moving sideways at all.

In Super Smash Flash 2
In Super Smash Flash 2, every attack that sent opponents downwards was a spike, until the addition of meteor cancelling in demo v0.8a, where every attack that sent foes downwards became a meteor smash, instead.

Spikes were re-introduced to SSF2 in Beta 1.2.3.1. Attacks with knockback angles higher than 300° instantly become unable to be meteor cancelled, and are, by definition, spikes.

Trivia

 * Before spikes were re-added to SSF2, 's down aerial contained a variable that turned its tipper hitboxes into spikes. The variable did not work, however.