As soon as the series began, fans were already intrigued by Death Note's cast. Light, Ryuk, and L became some of the most popular faces in manga and anime. As the story progressed, more compelling characters were introduced.
After L's death, his successors became Light's next opponents. Mello was an incredibly smart yet emotional orphan from Wammy's House. He was quick to take actions, most of which impacted the other characters a lot. From kidnapping Sayu to destroying his own hideout, Mello would do anything that he had to in order to prove he was worthy to be L's true successor.
10 Early Concept
In Death Note 13: How To Read, Tsugumi Ohba, the author of the manga, revealed interesting info about many of the series' characters. Before coming up with the idea for Wammy's House, Ohba considered making Near and Mello either L's brothers or sons. Though this would have been very interesting, the story would have had been quite different compared to the final product.
9 Second Smartest
While Mello had ambition like L, there was always one kid who seemed better than him at the orphanage. Near was able to plan things far in advance and even used Mello to help him in his goals. Feeling inferior to Near, he never wanted to work with him and left Wammy's House once L died. Though Mello was smart enough to manipulate the mafia, get the notebook, and even outsmart Near at times, he always felt like he was in second place whenever his opponent made a move.
8 Chocolate
While L loved sugar and Near enjoyed playing with toys, Mello constantly ate chocolate. Every kid from Wammy's House had quirks and this was his most recognizable. When he first spoke to Soichiro, he purposely ate chocolate so Near would know that he got his hands on the notebook first. L must have been telling the truth when he said that eating sweets wouldn't raise his weight.
7 Mafia
When they learned that Kira killed L, Near and Mello chose to walk different paths in life. Near would go to the United States and become the leader of the SPK while Mello joined the mafia and became one of its most trusted members.
He may have played the part well, but Mello was only using his new comrades to get the notebook. They were simply the pawns that he was playing with in his game.
6 Real Name
Like the other kids at Wammy's House, Mello was given a fake name to hide his identity. Lawliet was L's real name and Nate River was what Near was once called. As for Mello, he was born Mihael Keehl. After Soichiro traded half of his remaining life for the Shinigami Eyes, he was able to see Mello's name. Though the chief made the deal in order to write Mello's name in the notebook, he hesitated and died before he could.
5 Connection To Lidner
Though he didn't want to work with Near, Mello actually joined forces with one of the other members of the SPK. Unable to pick between Mello and Near, Lidner worked with both of them in order to take Kira down. Unaware that she was also Mello's comrade, the SPK members were tricked when Mello pretended to take her as a hostage in order to receive the only photograph that he was ever in back from Near.
Each orphan from Wammy's House had their own photo and Mello forgot to take his with him when he left. Always having the intention to return it to Mello, Near held onto it. In return for his kindness, Mello gave him some information. Though Lidner and Mello weren't seen together much after that, they still helped each other and she was the saddest when he died.
4 Using Near
While Near sat on the sidelines for the majority of the series, he learned a lot from Mello. However, he never expected Mello to use him. After getting in contact with Mogi, Mello sent the task force member to SPK's headquarters. He had Near question Mogi while they were on the phone so Mello could hear the conversation without risking his life.
Due to Mogi refusing to answer Near's questions, this seemed to have been pointless at first. However, Near was able to convince Mogi and Aizawa of the possibility that Kira was Light, which turned out to be very useful in defeating the killer.
3 His Scar
When Soichiro hesitated to write Mello's name in the notebook, Mello used explosives that were in the mafia's hideout to get away. Though he killed Soichiro and escaped, Mello was also injured. The scar on his left eye became one of his most notable features while foreshadowing his death by fire and representing the half of L that Near could never be.
2 Matt
Besides Mello and Near, another kid from Wammy's House that got involved in the Kira case was Matt. He was Mello's only true friend and worked closely with him. When the two kidnapped Takada, he was shot to death. However, he wouldn't have to wait long to be reunited with his best friend as Takada would burn Mello, killing him. Though Matt didn't appear in the series for long, fans learned that he loved playing video games and had a crush on Misa.
1 Died For Near
Despite their rivalry, Mello would rather aid Near than Kira. When he learned about Near's plan, he kidnapped Takada in order to help him. If it weren't for this, Mikami would not have gone to the bank two days in a row to take out his notebook and Near wouldn't have made a replica of the weapon. If it weren't for Mello's death, Near and everyone else that went to the Yellow Box Warehouse would have died. Near honors Mello's memory by eating chocolate and acknowledging that he would have lost if it weren't for the only other person worthy of becoming the next L.