At some early point in the game, he gives a device that solves electronic puzzles to Shauna. He first appears outside the Prism Tower with his little sister, Bonnie, lighting it up. He will give TM24 (Thunderbolt) after being defeated. According to the television show Gym Freaks, he is currently developing a machine that enables him to run faster, which is apparently his worst talent. It also states that he has secretly started to save money to go to the amusement park in the Unova region. He is described as a genius, having been credited with the invention of Super Training. Despite this, many of his inventions apparently fail to work.
"Oh! Thank you again for coming. Allow me to introduce myself..."
"Bonnie! How many times do I have to remind you... It's not my own strength that matters, nor any other Trainer's. None of us would be here if it weren't for our Pokémon."
"She's right about that, at least. Let's both do our best in battle."
Upon being defeated
"Your passion for battle inspires me!"
After being defeated
"Oh, Bonnie... When will you learn there's no shame in losing? I'm glad whenever I get to learn something new thanks to strong challengers like this boy/girl here."
"Now, to the victor go the spoils! This Voltage Badge belongs to you!"
"If you have a Voltage Badge, you will be seen as a friend and equal by any Pokémon up to Lv. 70. And here. Take this TM as well..."
"Arghhh! Bonnie, you--! ... ... ... The future is now, thanks to science! Behold the machine that gives: Technical Machines! ...I just wanted to be able to say it, OK? At least once."
"Look, I'm not... It's not like I'm just trying to make myself stronger or... ... ... ... All I'm trying to do is enjoy every day to the fullest with my Pokémon, while doing the science that I love with my inventing."
Post-game
"How did the world look after defeating the Champion? I really want to understand it. The way the world looks to a real Pokémon Champion... I'm trying to invent a machine that will let me see it for myself."
"Oh! I'm glad that we got to meet yet again like this!"
Upon being defeated
"Your passion for battle inspires me!"
After being defeated
If giving the player an item: "The future is now, thanks to science! Power on, my new precious gift-giving machine... Mach 2!"
"I'm glad whenever I get to learn from other strong challengers. Thank you for the battle!"
If the player is defeated
"Looks like my Trainer-Grow-Stronger Machine, Mach 2 is really working!"
Gym Freaks
April: "Hello! It's time for Gym Freaks, your source for the hottest news about hot Gym Leaders in Kalos. So... I'm now in front of the Lumiose City Gym! ... Eeek! Clemont has arrived! He's cute! So cute! His glasses make my heart twinge! Clemont has secretly started to save money to go to the amusement park in the Unova region. Awww... I want to donate money to his park fund! Oh... He went inside the Gym... That's all for the on-site report. Good-bye for now, everyone."
April: "Hello! It's time for Gym Freaks, your source for the hottest news about hot Gym Leaders in Kalos. So... I'm now in front of the Lumiose City Gym! ... Yeek! Clemont has arrived! He's cute! So cute! His glasses make my heart flutter! Clemont is also known as a genius inventor. But even such a genius has something he's not good at. That is...running. Lately, he's been developing a machine that enables him to run faster. Oh... He went inside the Gym... That's all for the on-site report. Good-bye for now, everyone."
Clemont is first seen in Cyllage City alongside Grant. He gets a call from Bonnie informing him that one of the Electric-type Pokémon that they used to power Prism Tower during a blackout has gone missing. Grant then points Clemont to Grace, who he noticed sitting on a bench. They see her being taken away by Team Flare members. As he travels back to Lumiose City, Clemont reads up on Grace in various issues of Rock-type Magazine that Grant lent to him. He finds Grace's daughter, Y, and her friends chasing after an Electrike that had stolen Y's clothes. After the Electrike had been defeated and Y's clothes returned to her, the Electrike evolves into a Manectric.
Clemont introduces himself to the group, but they accuse him of being someone suspicious. Clemont denies these claims, and when X realizes that Manectric must be looking for something, Clemont offers to use his backpack to track down the item in question, a Mega Stone. In addition to the Mega Stone, Clemont also finds a Team Flare Grunt in a tree who was also aiming to get the Mega Stone. Clemont attacks the Grunt with his Aipom Arm and obtains the Mega Stone. The Grunt retaliates by having his Tyrunt chew the tree down so that it would fall on top of Clemont and makes off with the Mega Stone. After the Grunt escapes, Y helps free Clemont with her Rhyhorn. The Grunt's four Espurr are defeated and captured by Cassius, who heard the commotion and came to help. As Cassius' Gourgeist holds the three Espurr captive, Clemont's curiosity gets the better of him. He decides to check under the Espurr's ears in order to find out what is under them, but is sent flying by the unrestrained force of their psychic powers. An unconscious Clemont is later found by the Team Flare Grunt that attacked them earlier, captured, and then taken to Team Flare's Secret HQ.
After awakening, Clemont finds himself inside Team Flare's base and is greeted by Xerosic. Xerosic frees Clemont from his bindings and demands that the young scientist use his skills to build a machine for Team Flare that will allow them to absorb the energy of Xerneas. Clemont refuses and attempts to attack the scientist only to find his Poké Balls missing. Xerosic easily defeats the defenseless Clemont, knocking his glasses away. Xerosic then presents Clemont's Heliolisk as a hostage to force Clemont to comply. Sometime later, Clemont successfully finishes the machine, but is thrown into a garbage incineration chute now that Xerosic no longer has any use for him. In his attempt to figure out where he was dropped, Clemont uses his backpack's monitor and inadvertently finds out that Team Flare's base is in Geosenge Town. At the same time in Laverre City, a wild Klefki that Grace befriended presents X with the glasses that were knocked off of Clemont's face previously. With the glasses ability to connect with Clemont's backpack monitor, X also learns the location of Team Flare's base.
When the Gym Leaders and X's friends head to Geosenge Town to attack Team Flare's base, they find the ultimate weapon in the process of being activated. While the Gym Leaders attempt to keep it from opening, Tierno, Trevor, and Shauna head to the garbage incineration chute to sneak into Team Flare's headquarters. As they climb the chute, they are attacked by Bryony's Bisharp, but are saved by Clemont's Aipom Arm at the last second. Tierno's group thanks Clemont for saving them and return his glasses back to him. They head further underground, where the find the holding cell of AZ. Although initially intimidated by his large appearance, Emma appears to assure everyone that AZ is a nice person. After freeing AZ, everyone continues advancing until they find the ultimate weapon's control room. Clemont uses his Aipom Arm to throw Trevor, Tierno, and Shauna to where the ultimate weapon's key is placed in so that they can attempt to remove it.
Later, Clemont, along with Bonnie, Alexa, Viola, and Yvette, confronts Team Flare at Route 10 in order to free the captured Pokémon there. Together, the group manages to defeat all the members of Team Flare and rescue the captured Pokémon. After Team Flare is fully defeated, Clemont and his allies meet with X and his friends at Lumiose City to congratulate them on their victory. Clemont reveals that he encountered Shauna's missing Furfrou at Route 10 and returns it to her. He also gives Trevor the Delphox that he battled at Route 10 due to Shauna's Furfrou recognizing it as a friend.
Heliolisk is Clemont's only known Pokémon. It was held captive by Xerosic as a hostage to force Clemont to build a machine for Team Flare. Some time afterward, Clemont retrieved Heliolisk.
This Furfrou originally belonged to Shauna. It was caught in an explosion at Vaniville Town and was separated from its Trainer. Afterward, it found its way to the Pokémon Village, where it was captured by Team Flare in order for its life energy to be used as fuel for the ultimate weapon. It was rescued by Clemont and his friends and was later returned to Shauna.
This Delphox guarded the life energy extraction process on Route 10. It battled against Clemont and his allies in order to prevent them from stopping Team Flare from reactivating the ultimate weapon. Although it fought hard with powerful attacks, Delphox eventually fell during the battle. After the battle, Shauna's Furfrou guarded the unconscious Delphox, as it recognized it as the Fennekin that was with Trevor before being lost in an explosion. Realizing that it must be connected to X's group, Clemont took Delphox with him and gave it to Trevor.
Clemont Cards listed with a blue background are only legal to use in the current Expanded format. Cards listed with a green background are legal to use in both the current Standard and Expanded formats.