|This article is about a/an villain in Power Rangers Samurai and Power Rangers Super Samurai.|
- "Ooh-ah-ooh, there's no one left but Octoroo. Whoa! Whoa! Whoa! Well, so much for the boss's big plans. They've all gone down the drain!"
- ―Octoroo's final words before his "death"[src]
Octoroo is one of Master Xandred's two followers, an elderly cephalopod-headed figure with a staff. Octoroo can often be seen mixing medicine for Master Xandred. He most often says "Ooh-ah-ooh!" before his sentence as well as a habit of rhyming. Octoroo is often the one to select and send other Nighloks to concoct their schemes to raise the Sanzu River waters, second only to Xandred or Serrator. He feels that everyone on the ship should be allies, believing all Nighloks to have the same common goal(s).
Octoroo seems to be one of the smarter Nighloks since he is able to come up with complex strategies and counter-strategies with a large amount of knowledge and magic, and can make plans that are hard to follow, rash, and generally unpredictable. He also has some knowledge in medical techniques due to making large doses of medicine for Master Xandred's headaches. He is also a bit of an optimist, on account of him acting as a foil against Dayu's pessimistic persona. He also seems to know when he is outmatched in a fight and retreats when facing the Samurai Rangers. He is apparently considered trustworthy enough to know about Deker and Dayu's past. Due to this, Master Xandred feels that he is loyal enough to stay on his ship, and creates many barriers with his vast knowledge, ranging from disrupting communications to disabling morphers.
Octoroo has always been suspicious of, therefore never forming an alliance with Serrator. Later his suspicions are confirmed when Serrator betrayed Master Xandred. Octoroo values Master Xandred's life, over his own, even after Master Xandred attacked him, while he was trying to save Xandred from dehydration. It was he who saved Master Xandred, sinking Xandred to the bottom of the Sanzu River, before wondering how long it would take before Xandred was fully healed again. However as a result he found himself forced to work for Serrator who easily took over the ship unopposed. Octoroo tried to convince Serrator not to go through with his ultimate evil plan of flooding and conquering both worlds, but to no success.
After Serrator's destruction, Octoroo took over the efforts to flood the Earth as well as reuniting with Dayu. It was he who sent the Nighlok Fiera to the surface knowing that her fire had the power to destroy the head of the Shiba house (not knowing that Jayden was not the actual head), and later sacrificed half his lifeforce to Gigertox in order to grant him a third life against the Rangers, meaning that if he was ever destroyed he would not transform into a Mega-Monster.
When he heard about Deker's demise, he told Dayu that since Deker is gone she has nothing left to lose. Octoroo said that a new sad tune about Deker may be able to revive Xandred and increase his power. After Master Xandred returned and absorbed Dayu, Octoroo briefly mourned Dayu's demise because she was the one who cured Xandred's headaches whenever she played the harmonium. Also by absorbing Dayu's humanity, Xandred gained immunity to drying out and the Sealing Symbol. As a result, it allowed the Sanzu River to finally flood the Earth. However when Master Xandred was defeated by the Samurai Rangers, the river went back to the Netherworld, sinking the ship Octoroo was in. It is unknown whether Octoroo survived or not.
- He is similar to Finster from Mighty Morphin' Power Rangers.
- He is also similar to Kegler from Power Rangers Lost Galaxy.
- He also has a schemer personality like Jinxer from Power Rangers Lightspeed Rescue.
- He is also shown to betray Master Xandred a couple of times, much like Frax betrayed Ransik in Time Force. However, he is still the most loyal of Xandred's servants, though this is not saying much for the other servants.
- Octoroo is one of the few major Power Rangers villains to both survive the events of the season and not get redeemed.
- He sentai counterpart would be defeated by the Gokaigers in Goseiger vs Shinkinger, something that would only make sense if the Mega Rangers traveled back in time after gaining super mega mode, but Goseiger vs Shinkinger and Ep. 40 of Gokaiger were not adapted