Frax

Frax started as Dr Louis Fericks, a human scientist from the year 3000 who created a cure for the Venomark poison intended to kill Ransik. Fericks showed kindness towards Ransik, but in return, Ransik blew up Dr Fericks' lab, with him still inside, and stole all his Cyclobot technology. Ferricks survived the explosion, but gravely injured, he saw only one chance of survival and rebuilt his entire body into a robot - becoming Frax.

It is unknown how Frax later joined forces with Ransik, becoming his number-one Robot ally, but Frax, on the outside, turned out to be the ultimate loyal servant to Ransik who he called "Master", but in reality, Frax harbors deep resentment against Ransik for the things he caused to him in the past. Frax was also treated as vermin by Ransik, along with all the other Robots for being "Completely useless". Frax swore that one day he would get revenge.

Later in the series, Frax uses some stolen Trizyrium powder to synthesize a Trizyrium crystal and uses it to power up Tronicon, a Robot which Frax created in secret, but after causing much chaos, Tronicon is destroyed by the Time Force Rangers and Frax has to answer to Ransik. Soon after, Frax discovers the X-Vault, where the worst prisoners are contained. He releases many of them without Ransik's approval, including Venomark (an action that particularly angers Ransik due to their past history). As a form of revenge, he destroys all of his serum and runs away from Ransik, after confessing to him who he really was.

Frax goes into hiding and retreats to a large compound in the city where he begins constructing massive robots, run on powerful Trizirium crystals from Mr. Collins' lab. He plots to destroy Ransik, take over the city and make Robots the most superior beings. He constructs first Dragontron, which he sends to destroy the Time Force Rangers and capture the city for him, and it proves to be quite dificult for the Rangers to destroy, but eventually, Dragontron falls to their Zords, forcing Frax to make new plans to conquer the city.

Frax also tries to convert the humans into Cyclobots with a fitness liquid and a mutant (it is unknown how he got the mutant), but after these plans fail, Frax later constructs the robot Max Axe and finally his most powerful Trizyrium crystal-powered creation, Doomtron.

In the finale, Frax is caught by Ransik with the aid of Gluto. Ransik then steals Doomtron and imprisons Frax. Nadira, Ransik's daughter, comes to him after she begins to doubt her father's mission. Frax explains that the hatred and prejudice between humans and mutants is a vicious cycle, which also consumed him, and he urges her to break it before being taken away and having his memory erased.

He is then reprogrammed to obey only Ransik and to use Doomtron to destroy his enemies. Frax enters Doomtron at Ransik's command and he activates the robot, the two becoming one. Frax/Doomtron goes onto wreak havoc in the city and creates huge Vortexes which suck up the city buildings. He beats most of the Megazords but the Q-Rex's Trizirium crystal is neutralized and the Time Force Rangers are able to use the Quantasaurus Rex's lasers to destroy the Trizyrium crystal within Frax and ultimately destroy Doomtron, sealing all the vortex's in the sky.

Ransik and Nadira find Frax afterwards, only to see him fall apart and die, giving evidence that Dr. Ferricks has finally passed away.

Trivia
Although phonetically similar, Frax should not be confused with Thrax, who would not be introduced until many years later, in Operation Overdrive.