Comic Theme Time is a twist on the idea of a “Top Five” list. Instead of me stating a topic and then listing my top five choices in that topic, I’m giving you the topic and letting you go wild with examples that you think fit the theme.
Today, with Game 1 of the 2013 World Series looming, I wrote about Game 1 of the 1988 and the surprising origin of the term "walk-off," which is only 25 years old.
This made me think about other additions to the Marvel and DC Universes that came surprisingly late in the game. Like Alfred not being Alfred Pennyworth until the late 1960s or the Warriors Three not being called the Warriors Three until the mid-1970s or the Legion not having flight rings until nearly 100 issues after they debuted (and not having a "No Duplicate Powers" rule until the late 1970s!).
So what other good examples can you think of?