|Game Debut||Danball Senki (PSP)|
|Anime Debut||Episode 01|
|Appears in||Game, Anime|
|Voice Actor||Hiroki Touchi|
|Relatives|| Takeshi Hiyama (deceased)|
Mami Hiyama (alive)
|Occupation|| Professor Yamano's Assistant|
Bar Tender (outside cover)
Veteran LBX Player
Seeker Informative (former)
|Affiliation(s)|| Seeker (former)|
|LBX:|| G Rex (Break Over)|
Kabuto (temporary for Ban's training)
Ifreet (Break Over)
|Achievement(s)||Legendary LBX Player|
Ren Hiyama (檜山 蓮 Hiyama Ren) or commonly called 'Lex' is one of the support characters for Ban and his friends in Danball Senki. Later in the second half of the first season, it is revealed that he is mastermind behind the Kaidou android, taking the Innovator's plans for his personal vengeance. Thus, making him the true main antagonist of the series.
Hiyama has purple, spiky hair and usually wears a dark coat with a hoodie. He is medium sized for an adult and wears shades.
His outfit when working at Blue Cat's is akin to that of a bartender. He wears a red apron, vest, and dress pants.
For most of the series, Lex's attitude is that of a calm, supportive ally for the Seekers. During his "fight" against the Innovators, he usually gives secret routes to companies and assists Ban.
During the finale, it is revealed that Hiyama shot Kaidou Yoshimitsu, and was controlling Saturn's flight to N-City. His goal was to rewrite history by eradicating all major powers in the world. Lex believed that there was too much corruption in the modern world, and resorted to drastic measures to achieve his goals.
He runs a coffee shop in Mysore called "Blue Cats." It seems that he is aware of the contents of the briefcase given to Ban, as well as his father's work within the LBX world. After Hanzou loses to Ban and his friends, it's revealed the two are working together, but Lex isn't worried that Hanzou doesn't have the Achilles frame anymore.
Lex overwatches the battle between Ban and a brainwashed Kazu, only reacting as Achilles automatically activates V Mode.
The next day, he invites Takuya over. One of his spies in the Innovator confirmed that their next plan is to assassinate the prime minister. To stand a fighting chance, Ren was given a box from a mysterious owner with a letter: "borrow the strength of the children with the white LBX". Realizing that the LBX was meant for Ban Yamano and his allies, he gives the tip to Takuya, who brings them to Blue Cats Coffee.
During Takuya’s explanation of Junichirou’s kidnapping Ren assures the trio that Ban’s father wouldn’t be harmed because the Innovators would still need him alive and perfectly functional to assist their goals. He also warns them that the Innovators have power in the police, government, and several parts of the world, so they have to be careful. Later that night, Ren was unsure about telling the children about Angel Star, and realized alongside Takuya that Tougoru Kamiya was involved and holding the professor at Kamiya Craft.
Lex is considered a legendary LBX player (so it says at the back of is hooded jacket), which was revealed to the main trio at the beginning of the Underground Visdas tournament hosted by Blue Cats. Hanzou also reveals that the tablet with the opponent's data that he gave to Ban came from him. After the tournament ended with Ban's victory, Jin giving the boy the locations where Professor Yamano was being held and Rina's return with the plans to sneak into Kaidou's mansion, he agreed with Tyler to have the Seekers infiltrate and rescue the professor.
He taught Ban Yamano an attack function that he could use in Artemis, a tournament that he had also participated in with Gouda Hanzou. The two competed in the first round of Artemis’ A Block, where he let Hanzou take the lead. As Hakai-O defeats Zuul, Lex makes his move, commanding G-Rex to uppercut the second opponent’s Gladiator, causing a Break Over in one hit. The rest of the crowd shocks in awe at Rex’s legendary talents. The two eventually made it to the semi-finals.
As Hanzou tells the others about wanting revenge against the Innovators for the Rescue the Professor mission, he immediately reprimands him for focusing on a petty objective to win and reminds Ban that despite his feelings towards Jin, the Innovators’ deception should not be underestimated. Jin uses Impact Kaiser to finish the match early, but as Gouda dodges, Ren’s G-Rex punches the ground, causing a shockwave to nullify Jin’s hissatsu function. Following Gouda and Jin’s clash, he has G-Rex jump in and attack Emperor M2 with Gatling Bullet, knocking back Emperor M2. However, Jin recovers midair and fires more missiles, but Hanzou blocks G-Rex from the damage. Jin’s assault continues in one swing as Hakai-O breaks over, but Ren’s G-Rex nearly hits Jin’s before apparently stopping. He loses as Jin’s missiles finish off G-Rex. After the fight, Jin asks why he stopped his attack, but he tells the Emperor that he was slightly better than him by a small margin. He leaves the stadium and calls an unknown person, telling them “just as planned”.
From this point, Lex appears to be absent for a good majority of the season; occasionally contacting Ban, Takuya, and the Seekers. However, during the finale, it is revealed that he killed Yoshimitsu Kaidou, replacing him with an android that would follow his commands. Afterwards, he proceeds with his plan to destroy N-City, before being stopped by Ban. Ban convinces Lex that there is still good in the world, prompting Lex to rethink his actions and view of the world. Ultimately, Lex commits suicide by remaining on Saturn as it self-destructs, all while pushing Ban to safety.
- "Humans are not beasts. Humans are not gods. Humans should question what is means to be human. Exactly what is "man" here for? Humans that have become too smart, and have started controlling and ruling the world, as if they were gods. Humans who obtain great power devour the weak and pay no mind to their acts of cruelty, as if they were beasts. At some point, those people who progressed too far forget what is like to be human. I wanted the world to think about this, about the way humans should be." - Lex's message to the world.