The Esper Zombie Glitch is a glitch that renders an enemy unkillable.. The glitch is so-named from the fact that it was first discovered by users when playing as the Esper. As of Version 1.55, the glitch still persists.
The glitch is caused during combat while playing the Esper or Saiyan class. Choosing the Sense skill and/or the Focus skill as a Psion, or Awaken or Super as a Saiyan, then choosing the standard attack while the screen is still flashing will trigger the glitch if the attack reduces the opponent's HP to 0
Upon triggering the glitch, the enemy's HP will become 0, but it will continue to fight. It is now impossible to defeat the enemy. The only solutions are to run away, lose, or quit.