- One-Scene Wonder: Sid "the Squid", aka The Man Who Killed Batman, appeared in just this one episode and yet he's considered one of the most popular characters in the entire franchise.
- Retroactive Recognition: Listen closely and you'll recognize Sid's voice as Matt Frewer. He's been in a bunch of stuff (in the 80s, he was Max Headroom), but nowadays, he's known to Orphan Black fans as Dr. Leekie or to Disney fans as the voice of Panic.
- The Woobie: Sid the Squid. He'd veer into Jerkass Woobie if he wasn't so utterly pathetic.
YMMV / Batman: The Animated Series E51 "The Man Who Killed Batman"