Assassin

The Assassin is a Nobody from Kingdom Hearts II. It is first found in the 6th day of Twilight Town. The reaction command, Fail-Safe, allows Sora to grab one of the Assassin's arms and plunge the Assassin into the ground before it explodes. Axel mostly controls these Nobodies as well as Dusks. The self-destruct attack used by Assassins could be a reference to Axel's death, as Axel also sacrificed himself in battle.

Journal Entry
''An assassin. A high-ranking Nobody. It hides in the ground and attacks quietly from behind.''

''It cannot be attacked while it is in the ground. Parry its attacks to get it to surface.''

''When it starts running around, look out! It'll begin to unleash powerful attacks. Don't miss any chances to use the reaction commands to defeat as many as possible at once!''