42 is not the only answer!!!

'X's criminal modus operandi is so deeply ingrained into his personality that he is virtually powerless to stop himself from acting it out. He cannot simply kill his opponents when he has the upper hand, he has to put them in a deathtrap to see if he can devise a life and death intellectual challenge that the person cannot solve and escape. 'X's compulsion is quite flexible, allowing him to commit any crime as long as he can describe it in a ______.

Some writers have suggested that the 'X's compulsion stems from parental abuse that he endured as a child. After 'X' got high scores on some important tests in school, his father, unable to grasp the fact that his son was brilliant and believing he had cheated, beat him out of envy. This, in theory, left him with a strong internal desire to tell the truth, and prove his innocence. This desire manifests itself in the form of his obsession with ______. Other writers have suggested that his madness, as well as his descent into crime in general, have roots in a yearning to rise above the anonymity that he possessed in his youth.

Identify 'X'....

'X'-The riddler