If you're looking for anime similar to One Piece Special 2: Open Upon the Great Sea! A Father's Huge, HUGE Dream!, you might like these titles.
Many years before his showdown with Luffy, the 'Gold Lion' Shiki came face to face with the most legendary pirate of them all: Gol D. Roger. On one fateful day the two fearsome captains clash in a fight known as "The Great Battle of Edd War" and Shiki and his pirates are forced to flee the battle, regrouping later on. However, when Gol D. Roger is captured three years later, Shiki refuses to accept it and decides to go up against the navy to stop his execution and claim the pirate king’s life himself...
The world’s boldest buccaneers set sail for the great Pirate Festival, where the Straw Hats join a mad-dash race to find Gol D. Roger’s treasure. There’s just one little problem. An old member of Roger’s crew has a sinister score to settle.
While training under Rayleigh, Luffy must learn to harness the power of Haki in order to save the beautiful Boa Hancock and her sisters from a deadly escaped prisoner!
In a golden age of pirates, one young rookie namedMonkey D. Luffy is taking the world by storm. Setting out from his hometown in a small boat, Luffy is slowly gathering together a crew of strong friends to help him achieve his goal: to become the king of the pirates! Using his powers as a rubber man and relying on the strong bonds with his crewmates, the Straw Hat Piratestraverse the treacherous seas of the Grand Line battling tough enemies, preventing revolutions, exploring islands in the sky, and declaring all-out war against the world government. However, catching the eye of the marines has its price. With the full force of the navy on their tails, will Luffy and his friends make it to the second half of the Grand Line, let alone attain their dreams?
Luffy and the Straw Hats must face their former Davy Back Fight competitors on the mysterious island of Nebulandia – whose fog renders devil fruit powers useless. Foxy also has some new tricks up his sleeve, in the form of three new crewmembers. Do the Straw Hats stand a chance without their devil fruit abilities?
No sooner have Luffy and crew escaped the bounty hunters of Whisky Peak than they become the target of a sinister criminal outfit known as Baroque Works. But the Straw Hat pirates have bigger worries, now that they've agreed to protect a very important person in return for untold riches.