Be a Mon

You've become a Mon; now fight like one!

Be A Mon is a Mon sub-trope where a character is transformed into a tameable monster. This transformation can happen with the help of a Mon Machine. It may even be done by fusing a person with their Mon. There are different applications when fusion is involved (usually through The Power of Friendship), such as a Monster Upgrade or creating a Mon-Human hybrid. Sometimes, it just some sort of random event made by a Plot Device. This experience can lead to a stronger bond and understanding with their partner Mon. On the other hand, if it's just humans that can transform into monsters, they often use it as a means of combat. Still, there are instances where it can give the person a different perspective.

Not to be confused with being a man.

Examples of Be a Mon include:

Anime and Manga

Digimon Tamers' Biomerge Digivolution has the Digimon and their human partners fuse to reach their Mega Level. They are fully synchronized, but this can only be done in the Digital World or in certain circumstances in the real world.
- In Digimon Frontier, the children transform into one of the Legendary Warriors with their D-Tectors and a Spirit.
  - The original concept of Frontier had the Tamer and their Digimon fuse to achieve a higher form to battle in a Virtual Reality game.
- Digimon Data Squad has Bio-Hybrid D.N.A. Digivolution happens when certain humans modified with Digimon data use a Bio-Link Digivice to transform into Bio-Hybrids (A Human/Digimon fusion).
In the Pokémon anime, a witch transforms Ash into a Pikachu so he can better understand his electric mouse. Thus, he is dubbed by fans as Ashachu (Satochu in Japan).
- Pokemon Adventures' Bill is fused with a Rattata due to the PC Storage system accident.
- Pokémon RéBURST introduced the Burst technique, which allows humans to fuse with a Pokemon. A human needs a Burst Heart (a jewel that seals a Pokémon) and has undergone intense physical training. While using Burst, the human gains the appearance and the same attributes as the Pokémon while adding to their power.
The Mon Colle Knights can fuse with a Monster to control them in battle usually stopping Count Ludwig Presto Von Meinstein Collection's schemes.
Starting in Mega Man NT Warrior Axess, NetOps can Cross Fuse with their Navis in the real world. This can be achieved if they have a high synchronization rate and Synchro Chip while in a Dimensional Area.
In the 17th episode of Bakugan: Armored Alliance, Wyton and Batrix switch minds a la Freaky Friday.
Live On Cardliver Kakeru has Live Change cards that allows the Live On players to transform into monsters to fight in the games.
Chaosic Rune ES: Guran Douma has fused with the Chaosic Rune Monster, Mad Hand Pylon, that turns him into a Monster-Human Hybrid. He fights other Monsters rather than summons and controls them.
In Legendz, Mac McField transforms into Garion the Griffin due to a scheme by Ranshiin. Later, Mac is revealed and awakens as the Earth Saga and can summon Garion from a Talispod.

Fan Works

Fan fiction and fan art can portray characters transforming into Mon as a form of Author Appeal. Though, at times, it can be used to appeal to a particular audience.

Film

POKÉMON Detective Pikachu
- The R chemical when used with the powers of Mewtwo can fuse trainers with their Pokemon to complete Howard Clifford's goal of human evolution.
- Mewto reveals that when the Grenja attacked Harry, the car crash nearly killed him. So Pikachu offered his mind and body to save Harry, until Mewto could properly heal him later.
Guardians of the Lost Code have Synchronicity to achieve Warrior Forms, where Brijes and their human partner can fuse. The most powerful of these forms became known as the gods in the pas.

Video Games

Cassette Beasts has the human characters use tape recorder-like devices to transform into the titular monsters to battle.
In Pokémon Red and Blue the PC admin, Bill, was fused with a Pokemon due to an incident with the PC's teleportation system.
- The Pokémon Mystery Dungeon series has a human transported to another world filled with just Pokemon and is transformed into one.
Kingdom Hearts 3D is where Riku becomes Sora's Dream Eater in a scheme by the True Organization XIII to make Sora into one of their members. This is why he has the Dream Eater Spirit emblem on his back.
Y School Heroes: Bustlin' School Life: The YSP (Yo-Kai Special Power) Watch allows humans to transform into Yo-Kai heroes. They gain a unique appearance and are more powerful than the Yo-Kai.
Fate/Grand Order: Pseudo-Servants manifest by using humans as their vessels. This is because their Saint Graphs don't qualify as a Heroic Spirit. The fusion causes their personalities to merge into a hybrid of the two. It can also affect Skills, such as where they might upgrade or downgrade. Hosts are usually magi with personalities similar to the Servant's, plus their Magic Circuits, talent, and soul. They are actually identical to Demi-Servants, but they are created through a different method.
- Demi-Servants are humans who have taken the Saint Graphs of Heroic Spirits forced on between the vessel and the Hero. As a result, the human has more control over their abilities. On the other hand, the Heroic Spirit has minimal control over the Demi-Servant. The problem is how the person's mentality determines the Skills and Noble Phantasms they have access to. Still, they can develop if they can gain strong mental prowess.
Dragon Quest Monsters: Joker: Dr. Snap transforms into a monster called Dr. Snapped due to being corrupted by his Darkonium Orb.
In one Horde questline in World of Warcraft during theBattle of Azeroth storyline, the player is told to get rid of the Saurids that are harassing a merchant. At first, this seems like the same Twenty Bear Asses quests the player has done many times before, until one of the intended "bears" is Jani - "the Patron of Scavengers, the Lord of Thieves, the God of Garbage, Master of Minions, the Keeper of Secrets" but more importantly, a Mama Bear to the saurids. In order to teach the player a lesson, she turns him into a saurid, ordering him to steal the same merchant's hat to earn his true form back. Naturally, the player has no way to defend himself here, putting himself in the same position as those mobs he is so fond of slaughtering...
- If the player succeeds in that quest, he will meet Jani again a few more times, who will offer more quests that make use of this Trope, most of them involving playing pranks on officials and opposing Jani's rival, Yazma the Queen of Spies.
From the app game Raid: Shadow Legends; Pro wrestling diva Ronda Rousey gets so upset at being unable to defeat Fire Knight, she decides to enter the game and kick his ass personally. And yes, her avatar is a playable promotional Champion.

Western Animation

In Chaotic, Players use their Code Scanners to scan Creatures and transform them into Creatures when battling in one of the Domes. Still, Players can be afflicted by their current status, such as their physical health or mystical ailments.
Redakai's Kairu Warriors transform into Monsters by using their X-Drives to battle each other.
One of the Digata Defenders, Seth, merged with his Guardian, Kragus, after shards of the rock creature embedded into his body during his destruction. This causes Seth to grow rock-like armor while showing increased strength, but he becomes emotionally unstable. It was later reversed during the final battle with the Megalith.
- King Magnan fused with his Guardian, Voltanis, to gain immortality but became a crazy two-headed monster, Infinimora.
- Later on, Rion, Mel, and Seth gained the ability to merge with their Guardians due to an accident with the Dojo's power core. This fusion has better control and gives the Defenders their Guardians abilities.