Another hidden gem is The Lazurus Affair. This 1981 4 parter from Batman#332 to #335 shows the Lazurus pit for the first time. It also is the only time we see Dick Grayson as Robin team up with Catwoman. Robin goes to her for help after Batman takes off with Talia under suspicious circumstances and King Faraday gets involved. A must read for any Bat fans!
How about you take a turn with a DC villain profile, Leo?