Semi-spike

Semi-spikes are attacks in the ' series and in the ' series that send opponents at a very horizontal trajectory, which, due to the foes' gravity, can end up sending them slightly downwards. This is what makes it different from meteor smashes and spikes, which directly send opponents downward.

In Super Smash Flash
In Super Smash Flash, due to the instant-KO attack bug, all moves are able to semi-spike if the opponent is moving at a specific angle and speed. Up attacks and s, despite sending opponents vertically by default, will, most of the time, semi-spike foes.

In Super Smash Flash 2
In Super Smash Flash 2, the physics were changed to be closer to the official Smash games, causing moves to have different knockback tragetories, and thus, only specific moves can semi-spike opponents.