"Momentum Express Development Agency" is the one hundred and sixteenth episode of Yu-Gi-Oh! 5D's.

In order to gain some information on Iliaster, Yusei, Sherry and Bruno infiltrate Momentum Express. Inside, Yusei has a Concentration Duel against Clark.


Momentum Express

At the Momentum Express building, Yusei , Bruno and Sherry are present wearing Bolton & Company costumes. Yusei comments that this is where they will find some clues about Iliaster. "And find clues on my father's killers", Sherry adds.

A flashback shows the three of them with Jack and Crow at the Bolton & Company building. They ask Rick about what he knows about Momentum Express. Rick replies that Momentum Express is a private manufacturing company. Bolton & Company were commissioned by them to build an Ener-D engine. Duel Runners have such engines built in, but the original Ener-D was a large particle accelerator unit a couple of kilometers to tens of kilometers in diameter. Momentum Express is currently receiving financial support from the world, while he develops the Ener-D in the device. Bruno understands that Momentum Express are Bolton & Company's business giants. The company is shrouded in mystery and is reaching for some kind of space development program, Rick informs them. From just listening, Jack suspects something suspicious. Sherry asks why Rick can't investigate who they are. The company always have their doors closed, he replies. Rick gets an idea. He takes out his schedule. His company's staff are going to be testing the new engine soon, so he offers them to disguise themselves as his employees to sneak in. Yusei asks if Rick is really able to do this. Apologizing for what happened during the World Racing Grand Prix, he says that he can and is willing to cooperate while they try to find out the truth. Although, he asks that they fill out their report to him.


"Daniel", "Timothy", and "Eva" converse with Clark Smith.

When Yusei, Bruno, and Sherry arrive, they meet the company's Director, Clark, who asks if they are with Bolton & Company. Yusei, Bruno, and Sherry introduce themselves as "Daniel", "Timothy", and "Eva" respectively. Clark introduces himself as the one in charge here, Clark. He is a bit disappointed that Bolton couldn't make it, but says that Bolton and his company are still among his many friends and Bolton has created many great Duel Runners. Bruno thanks Clark for his kind words. Sherry asks if she's met Clark before, to which he replies no, he doesn't think so. As Clark moves on to the rest of the course, Bruno turns to Sherry and asks if she has met him before, to which Sherry replies "maybe".

As the four of them go up an escalator, a beam is shot vertically out of the building. The escalator stops and Clark says that it is not often the one to get Infinity up and running. Yusei, Bruno and Sherry look at each other and shrug, wondering what Infinity is. The elevator starts again and takes them to the top.

5Dx116 Infinity


A platform closes over the machine that fired the beam. Outside, Clark introduces the machine as Infinity. Yusei asks what it is and Clark explains that it is a matter transporter device, currently being studied by his company. Inside the machine, Planetary Particle run at high speeds to create a dimensional distortion. It then uses a wormhole, which is used to transfer material. If they continue to work on it, they may no longer need to send rockets into space. Yusei notices a Level 10 doorway nearby. Clark asks what the matter is, and he replies: "Nothing."

While Sherry compiles the report and Yusei test drives the Duel Runners through a series of tubes, Bruno hacks into the system in an attempt to find information about Iliaster. Bruno is surprised that he could hack from the inside and proceeds to investigate the inner workings of the company as much as possible. The concept design of Infinity appears on the screen of his computer as he does so.

Zora's house

5Dx116 Mishaps

Everything goes wrong.

At Zora's house, Lazar sits in front of a mirror with a hair brush in one hand, a hair straightener in the other and rollers in one side of his hair. He starts to worry and asks if the Momentum Express headquarters is really the home of the true enemy. He believes that sneaking in there is a fearless and reckless thing to do. However is there is a connection between Momentum Express and Iliaster, he is sure that Yusei will probably find it. He gets annoyed over the hair straighteners not working as usual.

Jack grunts and points out that while they are believing in Yusei, Lazar is worrying about his hair. There's more important things going on than that useless stuff. He proceeds to take a sip from his coffee, but is distracted by Crow whose earring has just fallen out while he was cooking. Jack calls that useless too and is about to get back to his coffee, but is interrupted again when Leo, who was cleaning a window, knocks over a vase of flowers, smashing it off the ground. Luna comes down from a ladder over this, but Leo tells her not to worry and the two of them collect the broken parts. Jack calls this useless too and finally gets the cup close to his mouth, only for the handle to break and leave the cup fall and spills hot coffee on himself, and he while tries shaking it off, Lazar's hair rollers pop out.

Momentum Express

Infiltrating the office

Yusei, Sherry and Bruno are at the restaurant Lucky Burger eating lunch. Bruno has his laptop out, but reports that they still haven't found any information on Iliaster. The person who should be in contact with the company is the director, Sherry says, and they only have a few hours left before the afternoon test run. They only place that they haven't investigated is Infinity, Bruno says. Sherry wonders if there is something there. However it will be hard to get information as the place is heavily protected, Bruno explains. Yusei remembers the Level 10 doorway he saw earlier and insists that what is important is behind there. But that place is only for certain employees, Bruno informs him, and if he wants to access the high levels, he will need to have an access key. Yusei asks if they think the director has one. Bruno had been thinking the same thing and points out that the director should be having lunch right now. Sherry sees what he is getting at and says that means the director's office should be empty. The three of them get up to go check it out.

5Dx116 Clarke Smith access key

The access card.

As Yusei, Sherry and Bruno rush to Clark's office, they are seen on security cameras. Once inside the office, they start searching for the access key. Yusei picks up a remote and turns on a TV, which splits into four screens showing surveillance of the hallways. Sherry looks through some drawers and finds the access card. Yusei suggests that they get going, but then stops Bruno as Clark appears on the surveillance monitors.

The Duel

When Clark enters the office, Bruno and Sherry are not in sight. Yusei says that he had been waiting for him. Clark identifies Yusei as Daniel and asks why he is here. Yusei replies that he has been waiting to Duel against him. On the desk behind Yusei, is a Deck in a glass case. Rick always says that Clark is proud of his Duels, Yusei says. Clark says that it is an honor.

Meanwhile Sherry and Bruno escape through a ventilation shaft. Bruno prays that Yusei will buy them some time and thinks that if Clark realizes that the key is missing, they will be done for.

Clark agrees to the Duel and takes the Deck out of the glass case. He claims to be a beginner and says that there will be some conditions attached to the Duel. The first is that there will be a different rule. Yusei wonders what this could be and Clark scatters the contents of his Deck across the table face-down. Yusei does the same at the opposite side the table. Clark announces that this shall be a Concentration Duel. Yusei is unfamiliar with this type of Duel.

Meanwhile, Bruno and Sherry slide the access card giving them access through a door.

Clark starts to explain the rules of a Concentration Duel; The basic rules are essentially the same. However players must flip cards and try to announce what type of card it is as they flip it. For example, if they want to Summon a monster, they must announce that they are doing that and then flip a card. If they card meets the requirements, they can Summon the monster. Otherwise it is placed back face down. The same is true for Spell and Trap Cards. The activation timing must be correct, otherwise it is put back. Only one Spell or Trap Cards can only be activated per turn. Any of the face-down cards can be flipped over. Yusei thinks that these are simple rules.

Clark declares that the second condition is that the winner takes all of the cards left on the table. He hopes that Yusei will accept. Yusei understands; Whoever loses loses their Deck. Yusei doesn't like the conditions, but needs to buy Sherry and Bruno time, so he accepts.

Since Yusei is unfamiliar with the rules of Concentration Dueling, Clark allows him to go first. Yusei declares that he is summoning a monster. He looks at his cards and thinks that the probability of flipping a monster is 50-50. He chooses a card and flips it, but it turns out to be "Future Battle", which is a Trap Card. Since it is not a monster, Clark tells Yusei that he must put it back face-down. Yusei thinks that this means he won't even know the location of cards he incorrectly turns over and puts it back thinking that it was a waste. Yusei then declares he is activating a Spell Card and flips over "Release Restraint Wave". Although he has drawn the type of card he declared the timing is incorrect; "Release Restraint Wave" must destroy an opponent's Equip Card, but since Clark has none, "Release Restraint Wave" cannot be used, so it is put back face-down. Yusei finally declares that he is activating a Trap Card, but flips over "Max Warrior", which is a Monster Card, so it is flipped face-down again. Yusei ends his turn.

5Dx116 Concentration Duel

The Concentration Duel.

It would be a waste to activate a Spell or Trap Card, Clark thinks and believes that Yusei already understands the rules of the game. Clark begins his turn. He declares that he is Summoning a monster. Yusei is surprised because the odds of activating a Spell or Trap Card should increase before Summoning a monster. Clark flips over "Hexa Knight". He claims that luck has helped him pick this monster. Although it is Level 6, its effect allows it to be Normal Summoned, without Releasing, since Yusei controls no monsters. Yusei failing to Summon a monster has given him good fortune, he says. Clark attacks Yusei directly with "Hexa Knight", lowering his Life Points to 2200. Clark ends his turn.

The key to winning involves drawing a monster Yusei thinks and this turn he knows where "Max Warrior" is. Yusei declare that he is Summoning a monster and flips over "Max Warrior". Clark comments that it and "Hexa Warrior" both have the same ATK. However when "Max Warrior" attacks an opponent's monster, it gains 400 ATK due to its effect. "Max Warrior's" ATK rises to 2200 as it attacks "Hexa Knight", destroying it and lowering Clark's Life Points to 3600. Clark then explains "Max Warrior's" other effect, which halves its ATK and DEF, until Yusei's next turn. The ATK of "Max Warrior" drops to 900. Yusei declares that he is activating a Spell Card, but flips a Trap Card, "Scrap-Iron Scarecrow", so it is flipped back face-down. However Yusei now has a way to block an attack next turn. He then declares he is activating a Trap Card and flips over a Spell Card, "Prevention Star". Clark wags his finger saying it can't be used, so it is flipped back face-down. However, Yusei thinks he has now developed a winning strategy; He plans to equip "Prevention Star" to "Max Warrior" next turn, which will allow him to use "Release Restraint Wave", which will destroy all of Clark's Spell and Trap Cards.


Clark Smith's rigged cards, shining with their corresponding card type.

Clark remarks that his opponent has done well but thinks that it would not win him the game. In his glasses, the edges of Clark's cards briefly shine yellow, green, or red: each of these correspond to Monsters, Spells, and Traps, which was why Clark kept getting the cards he needed. Clark declares he is activating a Spell Card, and flips over the Spell Card, "Fair Exchange". Yusei is surprised that Clark got it right again. Clark again credits his success to luck being on his side. "Fair Exchange" lets him send three cards from his Deck to the Graveyard and send cards equal to their combined Level from Yusei's Deck to the Graveyard. He looks at the table to choose 3 cards to send. He flips up a "Decago Knight", who is Level 10. Yusei gets suspicious when the second card Clark turns over is another "Decago Knight", but Clark calls it a coincidence. Clark says that he cannot wait to see if he gets a third one. He turns over the third "Decago Knight" and starts laughing. Yusei objects that that is impossible. Clark holds his hands before the three "Decago Knights" stating that God has apparently brought him a miracle. Yusei looks unconvinced. The combined Level of his 3 monsters is 30, so Yusei must send 30 cards to the Graveyard. Clark holds up his hands as he says this and then slams them on the table, causing 30 of Yusei's cards to bounce up and turn over. Among them are "Prevention Star", "Release Restraint Wave" and "Scrap-Iron Scarecrow". Yusei gathers up the 30 of them and puts them aside. Clark activates the effect of "Decago Knight". Since there are 3 of it in the Graveyard, he is able to shuffle them into his Deck. He collects all of his cards, puts them into a pile and scatters them across the table again. Finally Clark declares that he is Summoning a monster and flips over "Triangle Knight". He ends his turn.

Yusei starts his turn and the ATK of "Max Warrior" returns to normal. Clark has correctly declared the type of card 6 times in a row and even turned over the same card 3 times in a row, Yusei thinks and wonders if that is even possible. He calculates the odds of guessing the 3 cards in a row to be 10,000 to 1. Yusei is convinced that Clark has the game rigged.

Yusei looks at their two monster and thinks if he attacks Clark will counter and if he falls for another one of Clark's tricks he will lose. Clark asks Yusei what is wrong and reminds him that it's his turn. As Yusei wonders what he can do, the lights flicker off. Clark says not to worry; the power shortage was caused by Infinity. Yusei notices the sheen on Clark's cards reflected in his glasses and realizes how his plays were so accurate.

Elsewhere Sherry and Bruno are working on a computer, which blacks out. Bruno understands that this was caused by Infinity. The lights quickly go back on and the computer screen returns to where Sherry had left it and she finds a file on Iliaster. She inserts a flash drive and starts to copy the file over.

Yusei says that he has the mystery solved and Clark asks what he means. Yusei announces that he is Summoning a monster and flips over "Junk Synchron", who gets Summoned. Yusei uses its effect to Special Summon "Sonic Chick" from his Graveyard. Clark is stunned, surprised that Yusei managed to use an effect on his Graveyard to get 2 monsters at once. Yusei tunes "Junk Synchron", "Max Warrior" and "Sonic Chick" and chants "Clustering wishes will become a new shining star! Become the path its light shines upon! Synchro Summon! Take flight, Stardust Dragon!" as he Synchro Summons "Stardust Dragon". Clark sees that Synchro Summoning a monster is easier as the Extra Deck is not affected by the table. Yusei declares that he is activating the Trap Card, "Future Battle" and is able to flip it over as he knew its position from when he flipped it earlier. This allows him to Special Summon a card from Clark's Deck at random. If it is a monster, it is Special Summoned to Clark's side of the field and "Stardust Dragon" must attack it. If "Stardust Dragon" destroys the monster, Yusei can continue to use the effect of "Future Battle". Yusei points to one of Clark's cards, which turns out to be "Decago Knight". "Stardust Dragon" attacks and destroys it with its "Shooting Sonic" attack, lowering Clark's Life Points to 2100. He uses the effect of "Future Battle" twice more, each time selecting another "Decago Knight". Clark's Life Points are dropped to 0.


Clark asks how this happened. Yusei responds that Clark's "useless tricks" won't work on him and picks up the remote control. Clark denies cheating, but Yusei asks "then what's this" and pushes a button on the remote, causing the lights in the room to go out. He explains that during the power outage Clark's cards were reflected in his glasses. Clark admits to being beaten and calls Yusei by his real name. Surprised, Yusei asks how he knows this.

Clark switches on the monitor and shows footage of Yusei, Bruno and Sherry in a hallway. His company's security is about being safe, he says. Sherry is highlighted and her facial structure matches one they have on file. data on Sherry pops up. Her ID number, name and sex are RN_10225479, Sherry LeBlanc and female. Her date of birth, age, address, occupation, career, birth place, height, weight and blood type are all unknown. The monitor shows Yusei opening a door. His fingerprint is read and matches one they have on file. Data on Yusei pops-up. His ID number, name, age, sex and birthplace RN_00001138, Yusei Fudo, male and Neo Domino City. For his career it says "Link". His date of birth, address, occupation, height, weight and blood type are all unknown. Clark explains that they examined their faces and fingerprints to find out who they were and knew who they were right from the start. He didn't think that they were going to do much, but confesses that he must have underestimated them.

Yusei accuses Clark of being involved with Iliaster, but Clark thinks Yusei should worry more about his friends right now. He pushes a button on the remote triggering an alarm. Bruno and Sherry get up and run from the computer they were at. This is shown on the monitor in Clark's office. Yusei runs out of the room to help them. He doesn't take Clark's Deck as a prize.


Infinity activates.

Yusei catches up with his friends, who show him that they have gotten hold of a file on Iliaster. They are spotted by Momentum Express employees. They run and Yusei leads them into a large room containing a shuttle. Sherry suggests that they hide inside the shuttle. When they get inside the door quickly closes behind them. They realize that it was a trap and run up to the front of the shuttle. They start banging on the window as the shuttle is transported across the room. Clark watches on his monitor and says that Yusei will now disappear between two periods. The shuttle stops over Infinity, which activates, causing Ener-D to swirl around the shuttle.

Featured Duel: Yusei Fudo vs. Clark

5Dx116 Clark VS Yusei

Yusei VS Clark.

This Duel is a Concentration Duel.

Turn 1: Yusei
Yusei declares that he will Summon a monster, but flips over a Trap Card, "Future Battle", and flips it back face-down. Yusei declares that he will activate a Spell Card and flips over "Release Restraint Wave". Since Yusei doesn't meet the Activation Requirements of "Release Restraint Wave, he flips it back face-down. Yusei declares that he will activate a Trap Card, but flips over a Monster Card, "Max Warrior", and flips it back face-down.

Turn 2: Clark
Clark declares that he is Summoning a monster and flips over "Hexa Knight" (CG Star6/1800/1200) which Clark Normal Summons in Attack Position without any Tributes due to Yusei controlling no monsters. "Hexa Knight" attacks directly (Yusei 4000 → 2200).

Turn 3: Yusei
Yusei declares that he is Summoning a monster and flips over "Max Warrior" (CG Star4/1800/800) which Yusei Normal Summons in Attack Position (Yusei's Deck: 40 → 39). "Max Warrior" attacks "Hexa Knight". Due to the first effect of "Max Warrior", it gains 400 ATK during the Damage Step ("Max Warrior": 1800 → 2200/800). "Max Warrior" destroys "Hexa Knight" (Clark 4000 → 3600). At the end of the Damage Step, the first effect of "Max Warrior" expires ("Max Warrior": 2200 → 1800/800). Since "Max Warrior destroyed a monster in battle, its ATK and DEF are halved and its Level becomes 2 ("Max Warrior": 1800 → 900/800 → 400; CG Star: 4 → 2).

Yusei declares that he is activating a Spell Card, but flips a Trap Card, "Scrap-Iron Scarecrow" and flips it back face-down. He then declares he is activating a Trap Card, but he flips over a Spell Card, "Prevention Star" and flips it back face-down. Yusei plans to use "Scrap-Iron Scarecrow" to negate Clark's next attack and he plans to equip "Prevention Star" to "Max Warrior" on his next turn, allowing him to use "Release Restraint Wave" to destroy all of Clark's Spell and Trap Cards.

Turn 4: Clark
Clark declares he is activating a Spell Card, and flips over "Fair Exchange", which allows Clark to send three "Decago Knights" from his Deck to the Graveyard and force Yusei to send cards from his Deck to the Graveyard equal to the combined Levels of the sent monsters. Each of the "Decago Knights" are Level 10 (Yusei's Deck: 39 → 9). Among Yusei's sent cards are "Prevention Star", "Release Restraint Wave" and "Scrap-Iron Scarecrow".

Clark activates the effect of "Decago Knight"" to return his three "Decago Knights" from his Graveyard to his Deck. Clark declares that he is summoning a monster and flips over a Monster Card, "Triangle Knight" (CG Star3/900/900) which Clark Normal Summons in Attack Position.

Turn 5: Yusei
On Yusei's Standby Phase, the second effect of "Max Warrior" expires ("Max Warrior": 900 → 1800/400 → 800; CG Star: 2 → 4). Yusei declares that he is Summoning a monster and flips over a Monster Card, "Junk Synchron" (CG Star3/1300/500) which Yusei Normal Summons in Attack Position (Yusei's Deck: 9 → 8). Yusei activates the effect of "Junk Synchron" to Special Summon "Sonic Chick" (CG Star1/300/300) from his Graveyard in Defense Position with its effects negated. Yusei tunes "Max Warrior" and "Sonic Chick" with "Junk Synchron" in order to Synchro Summon "Stardust Dragon" (CG Star8/2500/2000) in Attack Position.

Yusei declares that he is activating a Trap Card and flips over "Future Battle". Now, during the Battle Phase, Yusei can target one monster he controls and reveal the top card of Clark's Deck. If that card is a Monster Card, that monster will be Special Summoned in face-up Attack Position on Clark's side of the field, but if it's not, that card will be destroyed. The targeted monster must then attack the summoned monster this turn. If the targeted monster destroys the summoned monster by battle, Yusei can activate the effect of "Future Battle" again during this turn's Battle Phase.

Yusei activates the effect of "Future Battle" to target "Stardust Dragon" and select one of Clark's cards. It is "Decago Knight" (CG Star10/1000/1000), which is Special Summoned in Attack Position. "Stardust Dragon" attacks and destroys "Decago Knight" (Clark 3600 → 2100).

Yusei activates the effect of "Future Battle" again to target "Stardust Dragon" and select one of Clark's cards. It's "Decago Knight" (CG Star10/1000/1000), which is Special Summoned in Attack Position. "Stardust Dragon" attacks and destroys "Decago Knight" (Clark 2100 → 600).

Yusei then activates the effect of "Future Battle" again to target "Stardust Dragon" and select one of Clark's cards. It's "Decago Knight" (CG Star10/1000/1000), which is Special Summoned in Attack Position. "Stardust Dragon" attacks and destroys "Decago Knight" (Clark 600 → 0).


  • Yusei mentions that the probability of drawing the same card 3 times in a row is 1 in 10,000; this is quite accurate as the true probability (assuming a standard 40-card Deck) is 1 in 9,880.


  • In the original broadcast of this episode, Sonic Chick is in ATK mode instead of DEF mode when brought back via Junk Synchron's effect. This was fixed on the DVD version.

Featured cards

The following cards were used in this episode. Cards in italics debuted here.

Yusei Fudo
Clark Smith