Hitstun

Hitstun, referred to as hitlag in the code, is the period of time where after being hit by an attack, characters cannot do anything, but DI and/or tech if they come into contact with a platform, wall, or ceiling. It scales with damage, although starting values can vary. It begins right after hitlag ends.

Hitstun is an essential component of combos, as the basis of a combo is to have enemies not being able to interrupt or prevent the player's combo from happening.

In Super Smash Flash 2, unlike in the official games, hitstun is not cancellable (when excluding teching). When a meteor smash hits a grounded foe, hitstun is multiplied by 1.2.

Reeling
Reeling is the animation that plays during hitstun; characters enter a helix motion. Characters will enter this state after being hit by an attack that deals high knockback or a few attacks at high percentages. Once the knockback diminishes and the character slows down, reeling ends and tumbling begins. In SSF2, reeling happens commonly and with every character, but not every character currently has a proper animation for it.