Tyrann is a character in NieR RepliCant and NieR Gestalt (NIER). He is the shade inhabiting Kainé's body. The drama CD have also revealed that Tyrann was once called Yura Masayoshi and has a past connected to the original Kainé.
Yura Masayoshi was the commander of a small military unit for the "Counter-measure against Special Biological Organisms Department" that overran the Hamelin Organization and took their organic weapon No. 7 hostage. As a leader, he was bloodthirsty and absolutely ruthless. He used intimidation techniques and fear to keep his soldiers in line and didn't balk from using deadly force to make others cooperate with him.
The one who provided Yura with money and supported him in this movement was Kainé's grandmother, Kali. She orders him to guard her home against the incoming invasions of Red Eyes and Legion. In the end, Yura sacrifices all of his men as well as using Emil's abilities to try and save himself when the invasion couldn't be stopped. He went into hiding after this.
When individuals were being turned into Gestalts, Yura managed to join the ranks by changing his name to Tyrann. When the military figured out his scheme, they had Yura's Replicant destroyed. Unable to return to his proper body because of this, Tyrann spent the next thousand years invading other people's Replicants and using them until he destroyed them. He also fed his bloodthirst and need for control and power by slaughtering Shades.
This eventually led him to Kainé. When he was unable to convince the woman to give her body over to him, he instead made a deal with her. As long as she kept hating and killing things, he would simply reside within her heart and offer his help as she fought. If she showed a moment of weakness however, he would take her over completely.
It appears that just as Kainé comes to understand Tyrann, calling him "just a lonely soul, who nobody likes, and has to use hatred as a crutch" and that she too felt the same way as him, Tyrann likewise comes to understand Kainé. Thanks to this, Tyrann commits one of the first and only truly noble acts of his life in endings C and D of the game.
Though he is absolutely bloodthirsty and ruthless, Tyrann is a coldly intelligent person and much of this bloodthirsty nature may be born out of this. He seems to hold contempt for humans and how they treat one another, making frequent observations on their nature.
- His name “Tyrann” means “tyrant” in Swedish, Norwegian and German.
- He can recite the entire periodic table, as he has an excellent memory.
- The player does not hear Tyrann's voice until the second playthrough. The first time he is heard is when going through the Lost Shrine, describing the shades imprisoned within.
- Yoko Taro said in the third volume of Drag-On Dragoon Shi ni Itaru Aka that Nero is Tyrann's distant ancestor, though whether this should be considered canon or not is up to debate.
- SINoALICE has a character named Akiyoshi Yura (由良明義) being murdered in its Modern World scenario, which caused fans to speculate that the two continuities are possibly connected. Yoko said it's incidental and asked fans to not always draw connections between the IPs associated with his name.