Guard Break is a gameplay mechanic in For Honor. Using Guard Break allows the player to make an attempt at disrupting the opposing player's stance. If successful, the player can follow up with a grab and throw if they perform this additional maneuver quickly. Any hesitation will negate the opportunity.
A Guard Break attempt can be interrupted by the opposing player by using (X) on a controller or MMB on a mouse. This move shoves the hero, forcing them to take a step back and the attempted break becomes ineffective. As with the Guard Break, the timing of the interrupt is essential. It must be performed at the beginning of the Guard Break attempt, or it will fail.