Two Frame Punish

The Two Frame Punish is a mechanic and technique in Super Smash Bros. for Nintendo 3DS and Wii U in which an edge-guarder's attack is timed in order to punish the opponent on the two frames of vulnerability that occur at the beginning of a ledge grab animation.

Edge-Guarding Technique
As an edge-guarding technique the two frame punish is effective on characters with poor recoveries such as Little Mac and Ganondorf and against players unable to quickly react. Since it still counts as an edge grab, characters do regain their midair jump, which makes the technique less optimal, though it is still considered very impressive, particularly in competitive play, since it requires impeccable timing to pull off.

In competitive play
The two frame punish was originally known as the one frame punish before the edge frame data was more closely looked at. In competitive play, the player most well known for executing two frame punishes is Abadango, who impressively edge-guards Mr. R with a two frame punish using Wario at EVO 2015.