|This article is about a/an villain in Hyakujuu Sentai Gaoranger.|
- "What? W-what is the meaning of this? What?"
- ―Ultimate Org Senki's final words before his death
Ultimate Org Senki (究極オルグセンキ Kyūkyoku Orugu Senki, Thousand Demon): The King of all Orgs, the source of the Orgs' power after the Org Master was destroyed. Ultimate Org Senki was the final villain in the last episodes of Hyakujuu Sentai Gaoranger and was formed from the remains of the Highness Duke Orgs.
In the finale Senki was created when the Org Heart merges the remnants of the three Highness Dukes thus fufiling an ancient prophecy of the "Last Org Advent".
Stronger than Ultimate Org Hyakkimaru was, he overpowers the Gaorangers and destroys GaoGod and GaoHunter causing Shirogane's G-Brace Phone to disintegrate. He follows Shirogane to Animarium, destroys all but the original five Power Animals which then form into GaoKing, and then finishes GaoKing off destroying the other G-Phones and bringing the Animarium down. He then attacked the city. Since the Gaoranger witnessed him reform after failing to destroy him with GaoMuscle Striker, they realized that the Org Heart is his weakness and had to destroy it. Though Tetomu gave them an ancient sword to destroy Senki's heart, it was not enough. When all seemed lost the Rangers declare their humanity to Senki at which point the Power Animals are all revived and countless others arrive to help. They destroy Senki's physical form. The Gaorangers then use the Hyakujuuken to destroy the Org heart so he could not revive himself.
The Highness Dukes' combined weapon, which is also Senki's default is the All-Carnage Ogre Blade (修羅百鬼剣 Shura Hyakkiken). This weapon is the Highness Dukes' own version of the Gaoranger's Hyakujuuken, which is a combination of Shuten's axe, Ura's fan, and Rasetsu's knife and fork.
- Ultimate Org Senki was designed by character designer Yoshiro Harada.
- The face on Senki's body is a mark of the merging of the three Highness Duke Orgs and the senses they represent: Shuten represents the touch and sight, Ura represents smell and hearing and Rasetsu represents the taste and speech.
- Senki's wrists have armor/growths resembling the helmet of TsueTsue and the head of Yabaiba, while the body is colored similarly to their own; it is unknown why this is since they were not part of the fusion.
- However, it could be a play on TsueTsue and Yabaiba having the possibility of having a child of their own.
- Alternately, the costume was designed with the intent that they would be part of the fusion, when in reality they were killed beforehand; it is not clear if plans had changed or if the designer was unaware that they were not meant to be part of it.
- Hyakujuu Sentai Gaoranger