"Riddle Me That, Part 4 of 5"
*The Riddler's target is the scroll of Minos, and the location he has chosen as his base to break in the museum means that he'll have bypassed much of the security. With reporter Kara Harris in tow, Batman must circumvent the remaining security measures, which have been re-initialized - the two of them cannot separate, otherwise they'll set off an explosion which will kill them both. In time, they reach the scroll, but find it is untouched. The Riddler calmly walks in, backed by a number of heavies - he has used Batman to get past the security, and can now take the scroll with minimal difficulty.
Shortly before all this happened, Edward realized that Professor Buttery was using him to gain favor with code-breakers, passing Edward's work off as his own. Buttery also learned that Edward had been the Riddler - and now he has made him so much better. For interfering and cheating, the Riddler kills Professor Buttery, forcing the professor's son back to a life of crime, joining up with a costumed criminal. *Source: DCUGuide.com