It was a entertaining show with cool stories and fun memes. It tributes not just silver age comics but entertainment of all kinds that influenced comics and animation. The Bird's of Prey dance number was a fantastic example cabaret shows from golden age Hollywood, the best example in animation being MGM's Red cartoon shorts. Also, the episode produced the Huntress Too Fast meme.
The Sherlock homes episode had tons of pulp mystery and horror goodness. The multiverse story, featuring Batman vs Owlman, was an inspired way to introduce the Joker to the series.
The art style is really appealing, too.
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