Despite his body having still not fully recovered from his showdown with Basco, Captain Marvelous states the time has come for the Gokaigers to claim the Greatest Treasure of the Universe. However, Gai is worried about using the Great Powers that were stolen by Basco without the approval of their original owners. Suddenly, they are enveloped by a blinding light and before them appear Takayuki Hiba of Sun Vulcan, Sho Hayate of the Changemen, Dai of the Flashmen, Akira of the Maskmen, and Remi Hoshikawa of the Fivemen who reveal that they have watched over the Gokaigers during their travels and thus consider them worthy of their Great Powers. Meanwhile at the Gigant Horse, the Zangyack Empire's forces prepare a massive armada to conquer the Earth once and for all. Dairando reminds Insarn that once the invasion is complete, she would be punished for failing to protect Warz Gill, but Akudos Gill offers one final chance for her to redeem herself. Back on the Gokai Galleon, the Gokaigers are surprised to see Navi transforming into a door, remembering about Basco's comment about it actually being the door to the Greatest Treasure in the Universe, and they use the red heroes' keys of each of the other 34 Super Sentai teams to unlock it. Passing through the door, the pirates find themselves in a cave at the center of Earth that leads to an altar displaying the Greatest Treasure in the Universe. After putting their hands on the Treasure, they hear a voice that introduces itself as the Will of the Planet who communicates with them through it, informing them that they now hold the power to reshape the universe as they see fit. They think about using it to create a universe free of the Zangyack Empire, having their home worlds and the important people they lost returned to them. The Gokaigers return to the Gokai Galleon, but just as they are about to activate the Treasure, they are informed that by using its power, the power of the other Super Sentai teams will vanish as well and history will be rewritten as if they never existed. Still wondering about what they should do, they are attacked by Insarn piloting her own robot, the Great Insarn assisted by some enlarged Zugormin. Leaving Gai to deal with the Zugormin in Goujyujin, the rest of the team confront Insarn by themselves in Gokaioh. The Great Insarn manages to reflect Fuuraimaru's attacks with its defenses, but Gokaioh manages to break through them using the Gokai Power Bazooka attack with the Great Power of the Changemen and then damage it with the Gokai Aura Galaxy, performed with the Great Power of the Maskmen, before finishing it off with Shinken Gokaioh. Having her robot destroyed, Insarn launches herself at the Gokaigers with the help of some Dogomin sent by Dairando. But the Gokaigers use the Vul Eagle, Change Griffin, Green Flash, Blue Mask, and Five Yellow Ranger Keys to easily dispose of the Dogomin before finishing off Insarn with the Gokai Galleon Buster. Having disposed of the Zugormin, Gai joins the crew in their celebration before it is cut short when the Zangyack Empire, having sent Insarn just to buy some time for them, starts attacking with a fleet even larger than the one used during the Legend War, and the Emperor declares that he intends to destroy the space pirates and wipe out Earth's people.