SOURCE: http://mentalfloss.com/article/60213/visual-guide-all-37-villains-batman-tv-series
23. PUZZLER (MAURICE EVANS)
Not to be confused with The Riddler, Maurice Evans as Puzzler also likes to keep Batman and Robin confused with his clever puzzles, word games, and tricks. He’s often seen reciting Shakespeare and has a thing for aviation. According to Wikia, Puzzler’s appearance only came about because Frank Gorshin no longer wanted to play The Riddler during season two, so the show slotted Puzzler into these two episodes instead. Of course, John Astin would play The Riddler later in season two and Gorshin would return to the green tights in season three.
24. SANDMAN (MICHAEL RENNIE)
Portrayed by veteran actor Michael Rennie, Sandman’s two-episode appearance during Batman’s second season is often overshadowed by the fact that he’s working alongside the beautiful Julie Newmar as Catwoman. But fans should give the shifty Dr. Somnambular his due—the guy does have sleep powers after all!
25. COLONEL GUMM (ROGER C. CARMEL)
Roger C. Carmel’s performance as Colonel Gumm is mostly remembered for the villain’s penchant for wearing pink, being surround by pink, and being obsessed with stamps. The real memorable thing about Colonel Gumm’s two-episode arc, however, is the fact that the episodes feature crossover appearances by Green Hornet (Van Williams) and Kato (Bruce Lee).
26. BLACK WIDOW (TALLULAH BANKHEAD)
The most tragic thing about the great Tallulah Bankhead’s fantastic performance as season two villainess Black Widow in Batman is the fact that this would be her final on-screen role. Decked out in her signature black and red outfits, the character is unforgettable, whether it’s stealing from a bank or hanging out in her stunning spider-themed lair.
27. SIREN (JOAN COLLINS)
Siren, played by Joan Collins, begins her entrance into the world of Batman as a bit of a sidekick in The Riddler’s devious plan to take over Gotham City’s boxing game. By her second episode, however, the singing Siren makes a plan to uncover Batman’s true identity all by herself. Memorable for her beauty, luxurious outfits, and her ability to mesmerize men with her high-octave tunes, Siren makes an indelible mark on the series in the span of only two episodes.