Satan Enters Judas
"John 13:26 (NIV) Jesus answered, "It is the one to whom I will give this piece of bread when I have dipped it in the dish." Then, dipping the piece of bread, he gave it to Judas Iscariot, son of Simon. 27 As soon as Judas took the bread, Satan entered into him. "What you are about to do, do quickly," Jesus told him.
"Not told much more, but this may suggest that Judas wouldn't have done this on his own.
"This is perhaps also seen later in Judas' remorse.