: Moltor orders his new prisoner, Tyzonn, who had made a deal with him, to go with Bullox to steal the Parchment from the Rangers.
Tyzonn steals the Parchment. Red manages to get a corner part of the Parchment back, but Tyzonn gets away with the rest of it. The Rangers find a broken piece of a crystal that Tyzonn lost during the battle. A crystal of which he keeps in a little Pouch.
Dax scans the broken crystal piece, but finds no jewel signature of any kind. Mack wonders why the crystal is so important to Tyzonn.
Tyzonn stops at a small waterfall. Mack watches as Tyzonn stares at his own reflection. Tyzonn is shown to be very angry at himself.
Mack learns that Tyzonn isn't their enemy, and doesn't even know what the Parchment is for. Mack informs him that it leads to one of the jewels of the Corona. Tyzonn is shocked to hear that the Corona Aurora has been found, and knows that if Moltor gets the jewels, he will use the power to destroy everything that is good on all planets.
Tyzonn tells Moltor that he doesn't care about the deal, and he won't help him anymore. Moltor then strikes him, and Tyzonn becomes injured. Tyzonn tells Moltor that he will never get the jewels. Moltor tells Tyzonn that he is his servant forever. The two battle, and Mack jumps in. Red and Moltor battle. Bullox tries to blast Tyzonn, but Red deflects the fireball. Red and Tyzonn retreat into the forest.
Mack bandages Tyzonn's wound. Tyzonn tells Mack that he had brought shame to his planet by bowing to Moltor's will. Tyzonn gives the Parchment back to Mack, and when they hold the two parts together, the Parchment becomes one again.
Moltor and Bullox are close to locating them. The other four, searching for Mack, find green alien blood on the ground and know they are near. Mack and Tyzonn are encountered by Lava Lizards.Episode 12
: Mack and Tyzonn defeat the Lava Lizards. Tyzonn uses his ability to turn into Mercury. Mack turns off his Tracker to keep from being found, and asks Tyzonn to tell him the whole story. Mack gives the crystal piece to Tyzonn.
Mercurians -- Their power is known throughout the galaxy. Tyzonn came to Earth in search for something important to him, but his search was cut short. Moltor offered him to join his army. Tyzonn refused, and so Moltor crushed Tyzonn's crystal he wore on his wrist, breaking it into four pieces, then transformed Tyzonn into a reptilian creature. Moltor offered him a deal to do his bidding and he'll turn him back.
Mack and Tyzonn show up at the base. Mack explains that they can trust him, and that Tyzonn is going to help find the Touru Diamond. Tyzonn pours lemonade on the Parchment. The citric acid in the lemonade reveals the longitude and latitude location of the diamond.
The diamond is located in a volcano. Red and Tyzonn take the diamond. Bullox is destroyed by the DriveMax Ultrazord.
Back at the base, Tyzonn gives the Touru Diamond to Andrew. The diamond then shrinks to a smaller size. Sentinel Knight appears and congratulates them of their progress. They learn that they can use the two jewels they now have to help Tyzonn. Tyzonn is transformed back into his true humanoid form.
Tyzonn thanks them for their help and heads out to continue his search. But before he leaves, Mack gives him his crystal, which they had restored for himEpisode 13
: Two Fearcats, Mig and Cheetar, search for one of the jewels. Tyzonn joins a battle with the rangers, revealing his mission -- Tyzonn came to Earth, chasing the Fearcats. Just as the rangers are about to be hit by a blast from Mig's cannon, Tyzonn jumps in and uses his Mercury form to deflect the blast back at him. The Fearcats retreat.
Fearcats, A gang of intergalactic maniacs that have no respect for life.
After viewing the Fearcats, Flurious decides it's time to break out the Gyros.
Tyzonn has a flashback then leaves to go after the Fearcats while they search for one of the jewels. The team splits up to search for the jewel, and Ronny is captured by the Fearcats.
With Ronny tied up, the Fearcats plan to use her Tracker to free their Fearcat army from a Mirror Prison. Tyzonn and the others locate Ronny and battle the Fearcats. A Fearcat, Benglo, escapes from the Mirror and joins the battle. Tyzonn manages to get Ronny's Tracker back to her. Ronny morphs and breaks free from the ropes. She and Tyzonn then destroy the Mirror, destroying all the remaining Fearcats that were trapped inside.
After being blasted by the Drill Blaster, Cheetar uses the last of his energy to make himself grow. Cheetar is destroyed by the DriveMax Ultrazord. Mig uses his staff to destroy Tyzonn.
The team return to the scene and find Tyzonn in Mercury form.Episode 14
: The team head back to base with Tyzonn in Mercury form. Ronny drops the others off in the city while she takes Tyzonn to Mr. Hartford to try and save him.
Flurious tries his Gyros on two Chillers, but the power is to strong, and the Chillers are destroyed. Flurious sends Norg to find something that can handle the power.
Benglo and Mig attack the city to draw the Rangers out. Mr. H. uses the stabilizing unit used to stabilize metals and fabricating zord parts to try and bring Tyzonn back to normal. Tyzonn is back, and Ronny leaves to join the others. Andrew again asks Tyzonn to join the team, and gives him a morpher, but Tyzonn again turns him down.
The five Rangers battle the Fearcats. Mig takes out his staff, but then Tyzonn arrives. The rangers try the Drill Blaster Tri-Laser on Benglo, but Benglo breaks free. Tyzonn manages to take Mig's staff. He throws the staff to Yellow, and Yellow slashes the Fearcats with their own weapon. The two are forced to make themselves grow. The two are defeated by the DriveMax Ultrazord.
Norg brings Flurious the bodies of Mig and Benglo. Flurious places the Gyros inside the Fearcats. The two beasts are revived with more power then before. Flurious orders them to obey him. He sends them off to San Angeles to destroy the rangers. Benglo and Mig play along... for now.
Tyzonn informs them that he wants to join the team, but can't. He explains that many years ago, he was part of an elite team, Intergalactic Emergency Responders, but something happened. They were called to a cave-in. Innocent people were caught in rubble. He sent his team into the cave on a search-and-rescue mission while he stayed outside and searched for other injured people. They came out carrying the cavers with them, one was very upset. Tyzonn then learned that the Fearcats were blasting the cave from the inside. Tyzonn's job was to rescue everyone and not just the innocents so he sent his team back in, assuming that the Fearcats were trapped inside. But the Fearcats had escaped somehow. They blasted the cave, trapping the four rescuers inside. Tyzonn tells them that rescuing was his life, but he will never jeopardize another team.
As Tyzonn is leaving, Ronny runs after him and explains that what happened wasn't his fault.
The rangers arrive in the city to find that Benglo and Mig are back. The Gryos transform the two Fearcats into more powerful Fearcats, with new battle armor and weapons. The rangers seem to be unable to stop them. Then Tyzonn arrives in a new uniform. Tyzonn morphs into the Mercury Ranger and takes on the Fearcats. Mercury Ranger forces the Fearcats to retreat.Episode 26
: Tyzonn informs the team more about the cave-in that occurred many years ago. He tells them that Crazar was also there. He thought Crazar was buried inside because he didn't see her leave with Mig and Cheetar. His girlfriend, Vella, was lost in the cave-in. They were going to get married.Episode 28
: Tyzonn learns that Vella is still alive.Episode 32
: Tyzonn's search for Vella ends before it even begins as she and Norg make an appearance.