Instant charge

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Instant Charge (インスタントチャージ) or IC [RF gauge must be red or light blue, 22C during an successful attack]

If the RF gauge is in the red or light blue stage, pressing 22C during a successful, non-projectile attack will cause the character to perform an Instant Charge, which cuts the attack's animation short and completely empties the RF gauge. It is also accompanied by a split-second freeze, providing some bonus time to input the next attack. While most attacks are followed by a recovery delay during which the player cannot attack or defend, a well-timed IC lets you ignore this recovery time, allowing the creation of some particularly innovative combos.

Also, if the RF gauge was in the light blue stage, an IC will boost damage (normally about 50%+ proration) and increase the opponent's stun timer for the remainder of the combo. The increase in damage and juggling is directly related with the amount in the RF gauge at the time of the IC.

Flicker Instant Charge (フリッカーインスタントチャージ) or FIC

Certain attacks will let you perform an IC even if the attack is not successful (i.e. the attack completely misses the opponent), or if the attack is a projectile. Doing this is called a Flicker Instant Charge. An FIC has the same properties as an IC, except that it can only be done in specific frames of the attack, making the timing more difficult.