 If you liked
One Piece: Strong World
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 ...then you might like
One Piece: Episode A
|
Both short manga consist of backstories that are nice to read if you're caught up and waiting for the weekly additions to the ongoing story. While Episode A is specific about Ace and his adventures a few years before Luffy sets sail, Strong World is about the pirate world 20 years ago with lots of different (younger) faces seen.
You won't regret reading these if you're a true One Piece fan!
(If you can't find Strong World, try looking for OP Chapter 565.5.)