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Viper (バイパー, Baipà) is the original name of the holder of the Mist Arcobaleno Pacifier. They are a member of the elite Vongola assassination team, Varia, under their chosen name Esper Mammon (精子•マーモン, Espā Māmon). Known as the Varia's best spell caster, Viper has the ability to cast illusions as well as being able to locate any person by sneezing into a piece of paper (they carry a roll of paper with them); the spit or mucus that sticks to the paper shows a map leading to the desired person. Other than for the exception of the Arcobaleno Trials, Viper only works for money and is therefore represented as the sin of greed in Varia. They also have a dark green frog named Fantasma that lies on top of their head. By turning into a yellow ouroboros (a snake devouring its own tail that is also an alchemist's symbol) into a "halo" above them, Fantasma can give Viper the ability to fly in combat; they claim to have been trying to break the Arcobaleno curse, and had sealed their pacifier so that other Arcobaleno cannot sense them with the Mammon Chain, which also seals the power of Rings and Boxes and such. The chain is replaced by the Vongola by the cap that conceals the Rings' powers the same way as the Chains.
Both as an adult and in their Arcobaleno form, Viper is shown wearing a black outfit with a hood that covers their eyes, making it hard for fans to know their gender. From what little can be seen of their appearance before becoming an Arcobaleno, Viper had chin-length purple-lish hair and fairly white skin. They have two up-side-down triangle purple markings on their cheek that extend when they use their Arcobaleno powers.
As an Arcobaleno, they carry with them a roll of what seems to be tissue and uses it to create illusions to attack their opponents.
As the representative of Greed, they are materialistic and usually only work for money. Viper is generally an apathetic person but showed more emotion when they were trying to break the Arcobaleno curse, and vehemently expressed their desire to continue living. They tend to charge very high prices for their services.
Viper is one of the world's "I Prescelti Sette" (Strongest Seven) and was thus selected to become one of the Arcobaleno. At some point after they became an Arcobaleno, they joined the Varia and participated in the Cradle Affair. They then remained in the Varia for the following eight years until Xanxus was freed.
Plot OverviewVaria's plan in the beginning was to find all of the Vongola half-ring bearers on Tsuna's side and take the half-rings by force. Viper used their thoughtography to help the Varia members locate its equivalent member on Tsuna's side. Before a fight happened, CEDEF interrupted and it was explained that there would be an official battle for the rings. Members on both side will fight for the other half of their ring against the member on the opposite team who has it. Being bearer of half of the Vongola Mist Ring, Viper fought against the corresponding Mist guardian, Chrome Dokuro. They revealed themself as the Mist Arcabaleno and easily bested Chrome. When it seemed over, Chrome switched bodies with Rokudo Mukuro. Viper at first didn't believe it was Mukuro because they had heard of his imprisonment at Vendice, but they soon came to realize it was. Being the Mist Arcobaleno, the strongest illusionist, they were frustrated when Mukuro was overpowering them. They asked where Mukuro got this talented and Mukuro responded that he got his powers from Hell itself, irritating Viper, who didn't believe him at all, to the extreme. Viper was defeated and seemingly exploded, but Mukuro revealed that Viper had survived because they had reserved enough energy to escape as a precaution. As things progressed and events happened, Varia members are shown to have caught Viper from wherever they were regenerating to help fight at the main battle of the Ring Conflict, where whichever boss gathers all the rings first will succeed as the 10th Vongola Boss. As Xanxus and Tsuna fought, all the guardians were poisoned with a paralyzing illness that only obtaining the ring of their type would give them the antidote. Varia member Belphegor came and healed Viper and they set up a plan for getting all the rings by holding Chrome hostage. Their plan succeeded and even though their boss had lost against Tsuna, they gave him all the rings to seemingly take the win. The Vongola Rings rejected Xanxus and it became known that he didn't actually have Vongola blood. The Varia was disqualified but Belphegor revealed that backup was coming, backup that was only bested by the main Varia members. Three people arrived, nearly unconscious, and reported that all the rest had been defeated by Lancia. Being the only two members of Varia left able to fight, and being surrounded by all 6 of Tsuna's guardians, Belphegor and Viper surrender.
Viper is the third administrator of the Arcobaleno Trials. They and Belphegor enroll in Tsuna's school for a time, using the pseudonyms Monta and Himeko Hariyama. Later, Yamamoto discovers this when Himeko throws some of Bel's signature Knives to protect himself and Kyoko. Viper's Trial involves battling Tsuna, Ryohei, and Yamamoto. In the Trial, they use their special Ability: Mammon Mirage. Everyone was surprised when they heard Verde told Viper to test out a prototype Box Weapon. Reborn said that he had a bad feeling about this. During Verde's trial, Viper attempts to stop a Pawn missile from making it to Namimori, although their efforts were thwarted by a substance which was later revealed to be similar to the Non Tri-Ni-Sette, which Verde uses to capture the rest of the Arcobaleno, sans Aria. Unlike the actual Non Tri-Ni-Sette, the substance only paralyzes them, as opposed to outright killing them. It later turns out that the captured Arcobaleno were revealed to have been Illusions done by Viper as soon as they saw the substance released again when all the Arcobaleno were present.
Viper and the other Arcobaleno are called by Reborn to train Tsuna and the others. Viper is paired up with Chrome as his student. But, it seems that Viper hasn't taught anything to Chrome due to the fact that they don't get paid. So, right after they come back, after hearing their insults from Skull, they leave. However, they come back when Colonnello is searching for them and later helps Chrome to break Daemon Spade's Illusion. After Daemon and Giotto gave Chrome and Tsuna their inheritance, Chrome thanked them for saving her, and they said that she had improved, somehow. Shortly, they were picked up by Squalo and Belphegor who had searched for them everywhere because there was a job that required an illusionist.
At the ceremony, they noticed that Dino and Squalo had seen through Chrome's illusion of Yamamoto; however, they tell her that an illusion of that level can be only seen through by experts and assures her that she was doing well. At the last minute right after Tsuna and the others were defeated by the Shimon, they and the rest of the Varia along with Dino and Reborn, tried to stop the Shimon but was stopped in their tracks by Adelheid. Squalo requested for them and the rest of the Varia to chase after the Shimon right after they took Chrome away, but the Ninth order them not to chase after them.
Reborn sent a message to Viper and the other Arcobaleno about a hint about their curse. Viper was about to read the rest of the letter until Belphegor threw food at Viper which ruined the letter. They at first were confused of how to read the rest of the letter but then when Belphegor says that they will go to Jura in France to recruit Flan, Viper remembers the Pacifier Spring that was located near the area which could strengthen the light of pacifier, which could perhaps allow them to read the rest of the letter, and decides to go there along with the other Varia except for Xanxus. Viper and the others found Mukuro and the Kokuyo Gang also trying to recruit the young Flan, but Viper leaves soon afterwards, saying they couldn't care less about Flan. Viper heads to Pacifier spring and finds the other Arcobaleno, Fon, Colonello, Skull, and Verde. They said that some of the letters were unreadable, which can explain why some of the unreadable words on Viper's letter were not caused by the food. They say they should stack up the letters for the missing words to fit. After that, they know the information Reborn got during the battle against Daemon Spade, including the one about the mysterious Arcobaleno from the Vindice.
Viper strangely knows about the Arcobaleno with the transparent pacifier. Viper, along with the other Arcobaleno, minus Aria, are in a dream they are all having. They meet the mysterious man that they met before they became the Arcobaleno. The man asks if they want to be freed from the curse of the rainbow. Viper shows themself to be very passionate about breaking the curse, saying that it's been their dream for many years. The man says that the Arcobaleno that gives the best contributions will be released from the curse; he then reveals that the one that shows himself to be the strongest will be considered worthy. He states that the Arcobaleno cannot personally fight for themselves, but must get representatives to fight for them. Viper is then shown back at Varia headquarters requesting assistance from Xanxus, who replies that it depended on the situation, but is later on revealed to have accepted. They are later seen by Dino in Japan with the rest of the Varia, who were staying in the same hotel as the Chiavarone Famiglia. Viper is later seen in their residing hotel riding on Belphegor's head as they kidnapped Tsuna, calling Tsuna a brat; a while later, after Wonomichi arrives in the Varia's hotel room, Viper connects the former's appearance and clothing to Checker Face's. They then listen to the rules of the Representative Battle of the Rainbow.
Later, on the second day of the Representative Battle of the Rainbow, Viper tries to get Xanxus to fight Team Fon when they came to challenge them. Viper is successful and watches the battle, but is forced to release their curse with their Rainbow Wristwatch and use Hyper Mirage R to stop Fon from eliminating Xanxus and eliminating them from the battle, and announces that the rule they set for the battle was that the side that doubted their victory would self-destruct. They sent Fon and themself into illusionary space that they created and started to fight him one-on-one. However, Fon easily destroyed their illusions, making them doubt winning. Fortunately for them, Fon's curse release time has reached its limit and he returned to his baby form. Seeing this chance, Viper freeze Hibari's legs to prevent him from escaping Xanxus' attack, but Dino saved Hibari before the attack hit him. Xanxus ordered Viper to stand back since they're injured. Viper at first protested, but then reluctantly obeyed when Belphegor said that he wants to fight alone.
After the second battle ended with a draw, they and the other Arcobaleno are shocked to see Bermuda along with seven Vindices joining the Representative Battle of the Rainbow as the eighth team. Shortly after, they and the other Arcobaleno visit Skull at Namimori Hospital and discuss Bermuda, but find nothing on him. They then question Reborn his reason to join the Representative Battle of the Rainbow, but Reborn refuses to answer and instead tells them to ask Fon and Yuni . After the meeting dismisses, they go back to the hotel and are surprised to find their team has been assaulted by a Vindice.
On the third day of battle, Team Mammon is attacked by three Vindice. Viper goes into their un-cursed form and uses their Illusions to help their team escape the Vindice. They later meet with Reborn and the other Arcobaleno and opposes Reborn's idea of teaming up with Bermuda. This leads to a fight in which Viper accidentally hits Yuni with an illusionary attack.
Weapons and Abilities
Before they were turned into an Arcobaleno, they were a first-class psychic who added Illusions to their repertoire. It was seen they could also fly before they were turned into an Arcobaleno. Their psychic ability was telepathy, and they could also dowse things through pieces of paper so that they could find objects and people. As an Arcobaleno they still have all of their powers, but their Illusions have been strengthened, possibly because the Arcobaleno Mist Pacifer is an object of the Tri-ni-set that emits Mist Flames, creating real Illusions, and giving the wielder the Arcobaleno's ability to emit Dying Will Flames from their bodies. On one occasion, they even showed that they could teleport.
- Illusions: As the Mist Arcobaleno, their Illusions are first class; the only time they were defeated by another Illusionist was when they fought Mukuro during the Mist Ring Battle. Their most commonly seen used Illusions are Illusions of clones of themselves and the Illusion of tentacles.
- Viper Mirage: One of Viper's many Illusion abilities; they used this to surround Namimori with a series of mirages.
- Viper Mirage R: One of Viper's illusions that sets a rule on the target of which the illusion is cast on. If the rule is broken by the target, the target is instantly damaged with a multitude of deep cuts.
- Telepathy: One of their psychic abilities is telepathy, the ability to read minds.
- Thoughtography: The ability to locate any person by sneezing into a piece of paper; the spit or mucus that sticks to the paper shows a map leading to the desired person.
- Flight: Viper can fly because of their Animal Partner Fantasma's abilities, but they have been shown to be able to fly without Fantasma's assistance.
- Uroboros: Declared by Viper himself to be their strongest illusion, Viper unleashes multiple large blind eel-like creatures with large mouths and sharp teeth.
- Mist Starfish: It was one of the first Box Weapons that were created and appeared in the past. It was used by Viper against Yamamoto and Ryohei during the 3rd Trial. When used, many spinning Starfish that emit Mist-Flames come out of it. Those that break are fused together and create a single and bigger Starfish.
- The word "Mammon" is a term used to describe material wealth or greed, most often personified as a deity.
- They dislike being called by their given name, Viper. However, they don't seem to be bothered if Reborn calls them by that name.
- Their favorite word is 'greed', reflecting their own name.
- Their favorite food is 5-yen chocolate, while their favorite drink is strawberry milk.
- Their hobby is checking their deposit amount.
- They dislike leaving his debts unpaid.
- The reason why Viper collects money is because a human repeats the same life eternally.
- Viper's gender has been a debate among fans due to the use of gender-neutral pronouns used to describe them. They were grouped into the male character category in the third popularity poll, and their gender continues to remain as male in the official VIZ translations, though VIZ itself is not "official" and has become infamous for making many errors and not adhering to the original text when translating.
- Viper has a character song: Maboroshi no Arcobaleno.
- In the official English translation, Reborn and Colonnello said that their Arcobaleno Pacifier had a "sunny glow."
- In Drama CD: Namimori Radio, it was revealed that they and Belphegor once borrowed one of Leviathan's parabola when it was raining, but ended up being struck by lightning.
- In Haru Haru's Interview: Dangerous, it's revealed that like Fon, they cannot eat Mapo Tofu since they turned into a baby because it was spicy, which makes them choke and tear up.
- Viper only likes to work if they get paid. On a rare occasion, Viper works for free only if the situation is dire or it is their duties as an Arcobaleno, although they complain.
- Viper and Belphegor appear to be very close, as Viper avoids most of the Varia members and is mainly seen with Belphegor.