We'd already known that The CW's 'Arrow' would dip heavily into the DC reserves for its upcoming second season, even integrating a major 'Justice League' character, but has one of Batman's greatest enemies just booked a stay in Starling City? Potential spoilers of an upcoming episode title make an unmistakable reference to a famous 'Dark Knight' character brought to life in the Christopher Nolan film series, but which one?

According to an unconfirmed report from fansite TheGreenArrow.net (via Blastr), the fifth episode of 'Arrow' season 2 will bear the title of "The Demon's Head," a phrase well-known to comics fans as the English translation of "Ra's Al Ghul." The comic character served as the head of the League of Assassins (League of Shadows under Liam Neeson's 2005 'Batman Begins' incarnation), while 'Arrow''s Malcolm Merlyn (John Barrowman) previously made reference to the League's comic stronghold of Nanda Parbat.

According to the report, "The Demon's Head" will see Oliver up against "Awwal who is a Dark Archer, trained by Merlyn and [who] is after Lisa." The character of Lisa supposedly represents a mysterious new love interest for Oliver, though that information has not been verified either. Granted, the League of Assasins certainly seems a likely target for 'Arrow' season 2, even if Ra's Al Ghul himself remains too close to the Bat-franchise to actually appear.

In addition to teasing Metamorpho, The Atom and The Flash, ‘Arrow’ season 2 will pick up on October 9 some time after the events of season 1 finale “Sacrifice,” continuing its ‘Batman Begins’-influenced storytelling with the addition of new villains Isabel Rochev (Summer Glau), Brother Blood (Kevin Alejandro), Bronze Tiger (Michael Jai White) and DC character Sin ('The Killing''s Bex Taylor Klaus. Guest stars Colton Haynes (Roy Harper), Emily Bett Rickards (Felicity Smoak) and Manu Bennett (Slade Wilson) have all been upgraded to series regulars for the second year in Starling City.

We'll keep digging to see if Ra's Al Ghul could actually pop up in 'Arrow' season 2, but what do you think? Are Batman villains fair game for the emerald archer?