Y-Cancel
Introduction
"Y-Cancel" is an advanced tech in the Clash of Ninja series starting with GNT4 and continuing in all future installments, with a few adjustments. Y-cancels are performed by pressing 
after connecting with an attack to skip all ending lag of the attack. They have several requirements:
- is input during start up or active frames of the attack
- Y-cancels require and use 25% chakra
- The attack must have hit an opponent
- The victim is launched in the air with a normal or spinning launch- sweeps can't be Y-cancelled
- Projectiles can't be cancelled
- Starting in Clash of Ninja: Revolution, projectiles can be Y-cancelled.
Upon successfully Y-cancelling, a sound effect will play and the user will strike a pose (or Y-cancel stance). In GNT4, and column of light appears around the user. In the Wii games, a more subtle circle will flash around the attack.
Y-cancels are important in competitive play in order to lengthen combos and for staying safe from and punishing opposing KNJ's. Because KNJ resets the victim's state, an attacker may not be able to Y-cancel if the victim KNJ's quickly. Because Y-cancels require 25% chakra, links from a Y-cancel into 
will often require a just frame input if the user is not in crisis mode.
Y-cancels can be buffered! If you're having trouble getting Y-cancels out, try pressing or holding Y during the startup of the attack that you want to cancel.
Each Y-cancel adds an additional 5% damage scaling penalty to ensuing attacks, however this decay can be avoided by stance breaking.
Stance Break
"Stance break" is a related hidden tech to Y-cancels. By moving after entering the Y-cancel stance, the player can "break" their stance, returning to a neutral state and thus remove the extra Y-cancel damage decay. Normal combo decay will still apply. Left, right, and up directional attacks automatically stance break, so stance breaking is only relevant to neutral and down attacks. Furthermore, in terms of move selection, down takes priority over forward or back. Thus, the player can hold down-back or down-forward to easily achieve a stance break while comboing with down attacks.