The best episode written by Naoki Koga is "Retrieve the 5 Keys! The Straw Hat Crew VS CP9", rated 9/10 from 2 user votes. It was "directed by Takahiro Imamura". "Retrieve the 5 Keys! The Straw Hat Crew VS CP9" aired on 11/12/2006 and is rated 0.0 point(s) higher than their second highest rated, "Fukurou's Miscalculation! My Cola is the Water of Life!".
Luffy races to rescue Robin while the rest of the Straw Hats set off in search of the five keys needed to unlock the archaeologist!
Director: Takahiro Imamura
Writer: Naoki Koga
Chimney and Gombe show Luffy the secret passage that leads to Robin, and Franky puts on a display of raw punching power thanks to a few bottles of cola!
Director: Yoko Ikeda
Writer: Naoki Koga
Determined not to be defeated by the heinous hair of a devious lion, Chopper risks life and limb by summoning the power of his Rumble Ball for a third time!
Director: Yoshihiro Ueda
Writer: Naoki Koga
The madcap throwback continues as Luffy and the gang - along with a crowd of characters from the Alabasta arc - competes for a priceless treasure hidden inside a tasty snack!
Director: Yoko Ikeda
Writer: Naoki Koga
Franky has a painful encounter with monster Chopper, and Nami gets scrubbed too clean to fight! Meanwhile, Spandam accidentally invokes the deadly Buster Call!
Director: Hiroyuki Kakudou
Writer: Naoki Koga
Franky and Nami come up with a plan to stop Chopper's rampage, but it could prove deadly to the not-so-little reindeer. Usopp and Zoro are thrilled to finally be free of each other!
Director: Masahiro Hosoda
Writer: Naoki Koga
Sanji evens the playing field in his CP9 slugfest by introducing his wolfish opponent to the burning power of the devil's leg!
Director: Hiroyuki Kakudou
Writer: Naoki Koga
Zoro unleashes a demonic nine sword fighting style on his giraffe opponent, Luffy buys time for Franky by ascending to second gear, and Robin refuses to give up hope of being rescued!
Director: Yoko Ikeda
Writer: Naoki Koga
Luffy's battle with Lucci reveals the powerful secrets of the rubber man's second gear, and the Spandam's thoughtless Buster Call begins with a brutal barrage of cannon balls.
Director: N/A
Writer: Naoki Koga
Flashback to the dark past of Rob Lucci as the young boy learns to dispense a cold, cruel, and brutal brand of justice. Back in real time, Luffy's battle with Lucci threatens to destroy the navy fleet.
Director: Katsumi Tokoro
Writer: Naoki Koga
Thanks to a little help from what appears to be a mermaid, the Straw Hats find themselves reunited aboard an escape vessel, but the fate of Luffy and the Franky Family is yet to be determined!
Director: Hiroyuki Kakudou
Writer: Naoki Koga
Luffy lies battered and badly beaten, but Usopp's desperate pleas inspire the rubber-man to mount one final, furious attack on Rob Lucci!
Director: Makoto Sonoda
Writer: Naoki Koga
The Straw Hats are rescued by the unexpected arrival of a dear old friend, but they'll have to avoid a barrage of deadly cannonballs in order to survive!
Director: Hiroyuki Satou
Writer: Naoki Koga
The Straw Hats get some much needed rest and relaxation, Franky makes a big announcement, and Vice Admiral Garp tracks down his grandson!
Director: Hiroaki Miyamoto
Writer: Naoki Koga
Luffy gets the chance to catch up with his old friend Coby, Nami does some serious snooping, and Robin is paid a chilling visit from a terrifying face from her past.
Director: Yoko Ikeda
Writer: Naoki Koga
Zoro's day takes a turn for the crazy when his search for a new sword is derailed by a couple of meddling orphans!
Director: Keisuke Onishi
Writer: Naoki Koga
Brook tells Luffy that he is glad to be alive and asks if he can join the crew, which Luffy approves of. All the Straw Hats are shocked by this, except for Zoro, who is sleeping, and Robin, who knew Luffy would accept him no matter what, but they nevertheless welcome him to the crew. Two days later, Usopp and Franky make a grave for the dead Rumbar Pirates, and Zoro lays the broken Yubashiri at the grave. Nami gets a Vivre Card from Lola, which points the way to Lola's mother, a pirate in the New World. Luffy takes out the piece of paper he received from Ace, which is also a Vivre Card, and learns that as it is burning and shrinking, Ace's life is in danger. Believing that Ace can get out of trouble on his own, Luffy decides to head onward rather than go to rescue him, and the Straw Hats sail away from Thriller Bark. As the Luffy and his crew sail away, three enormous and mysterious figure appears in the fog, looking over Thriller Bark.
Director: Yutaka Nakajima
Writer: Naoki Koga
Luffy and the Straw Hats agree to help a mermaid rescue her friend, but the mission gets dangerous when a gang of flying fish dive bomb their boat!
Director: Sumio Watanabe
Writer: Naoki Koga
The Straw Hats' new ship gets a name, and Franky shows off some of its special features as the gang goes sky high to avoid being sunk by the marines!
Director: Tetsuya Endo
Writer: Naoki Koga
The captain of the Phoenix Pirates loses his will to fight, and the Straw Hats get trapped in a field of icebergs by some figure skating bounty hunters!
Director: Takahiro Imamura
Writer: Naoki Koga
After beating the zombies, the Straw Hats learn that one of the Shichibukai, Gecko Moria, has been stealing people's shadows and using them to revive zombies. After they leave, Absalom rallies the zombies together for the Night Attack, while the ghosts from before return to their master, a Gothic Lolita-style Ghost Princess Perona. Gecko Moria himself, a massive, giant-like man, is awoken. The Straw Hats come to the realization that Thriller Bark is not an island, but rather, a massive ship!
Director: Yoshihiro Ueda
Writer: Naoki Koga
Despite Absalom's attempts to halt Lola and abduct Nami to be her bride, both intents failed as the latter flees from Lola with Usopp and Chopper unable to slow the warthog zombie down. While the Wild Zombies disrespected his orders for them to not harm Nami, Absalom puts the lot in their place while venting his bad mode on Inuppe by blasting him into a wall for his insolence. At the same time, Franky and Robin buy some time against the Taralan and the General Zombies by the former destroying the bridge to trap the zombies in the courtyard while Robin flies them to the area of the castle behind Taralan. As Taralan was about to pursue them, Brook suddenly falls from the sky.
Director: Hiroaki Miyamoto
Writer: Naoki Koga
With their goals in mind, Luffy, Sanji, Robin, Usopp, and Chopper go after Nami and Moria! Meanwhile, Franky and Zoro head toward Brook. However, Hildon tells the others of the Straw Hat's plan.
Director: Katsumi Tokoro
Writer: Naoki Koga
Having deduced that Perona used her Horo-Horo powers to project her spirit, Usopp attempts to fire an attack at it. But the attack appeared to miss with Perona producing a Special Hollow bomb to hold Usopp while she returned to her body. Usopp luckily uses an Impact Dial to absorb the explosive force, using it to take out the Wild Zombie Hippo Gentleman with some injury as consequence. Usopp then reveals that he actually fired an adhesive on Perona's body, beating her by scaring the trapped girl to death with toy cockroaches and an inflatable ten-ton hammer. As Chopper begins to notice Jigoro and Inuppe acting less like Zoro and Sanji, Oars undergoes the same transition and makes his way back to Gecko Moriah. Meanwhile, Zoro and Ryuma's fight is getting intense as Brook tells Franky that Ryuma is actually fighting for real.
Director: Tetsuya Endo
Writer: Naoki Koga
As Abalsom makes another attempt to finalize his marriage to Nami, the other Straw Hats are fretting over Oars hunting them all down. Oars assumes he is kill the Straw Hats and attacks Sanji upon identifying him from his badly drawn wanted poster. While Oars lacks any Devil Fruit power, he is able to use Luffy's attacks to smack Sanji into a building. Oars was about to crush Sanji when Usopp used his Fire Star to set the zombie's head on fire, only to provoke him as Zoro and Franky attempt to fight him. But Oars is too fast and overpowers everyone before destroying bridge where Usopp, Chopper, and Robin were standing. As a wounded Usopp cursed "Luffy" while lying on the ground below alongside his teammates, Oars stood over the seemingly defeated Straw Hats while proclaiming that he is a servant of Moriah. Elsewhere, Luffy's continued pursuit of Moria leads him out of the manor and into the forest.
Director: Sumio Watanabe
Writer: Naoki Koga