Deadlock

Deadlock (デッドロック) is a group comprising of espers whose power development had reached a standstill and would not progress any further. They are a minor antagonistic organization in Shokuhou Misaki and Kamijou Touma's shared backstory, leading directly to the latter being incapable of remembering Misaki after meeting her.

Principles
The group is composed of students whose power development had reached a standstill and would no longer progress any further, hence their name. Unlike Skill-out, who are usually composed of solely Level 0s, it is implied that Deadlock has and is willing to recruit anyone, level 0 or above, as long as they are below Level 5.

Deadlock believes that the AIM Diffusion Field that is emitted by espers, especially those of the Level 5s, affects their development, preventing them from advancing in the power curriculum program. Due to this, Deadlock keeps an eye on Level 5s and occasionally put together a suicidal plan to crush them. In order to correct the unfairness that these espers unknowingly create due to their AIM Diffusion Fields that they emit without meaning to, Deadlock believes that killing these espers is the only solution. The only known instance of them attacking a Level 5 is the one they made against Shokuhou Misaki in the summer of the year before the main story.

Despite this, as Touma pointed out, Deadlock doesn't have any proof that espers like Misaki affected their development and are simply blaming others for their failures. However they are so convinced with themselves that any form of guilt or conscience can be disregarded by blaming it on an esper's AIM Diffusion Field, as shown when one of them blames Misaki for the guilt he is experiencing. In reality however, the reason why they do not advance is because of the Parameter List.

Deadlock was not without some code of honor as they had given Touma, as a level 0, a form of respect for his selfless decision. While they at first had tried to convince Touma to surrender, as he would be allowed to leave unharmed, Touma declared on how he stands firm in protecting Misaki knowing she needs his help; Deadlock had neither looked down upon nor ridiculed Touma's choice, as they came to see the deep resolve Touma had showed them. Instead they accepted, admired, and commended Touma for his courage, seeing him as a possible inspiration of what they could have become, as they began to attack both him and Misaki where Deadlock had wanted to witness how far Touma's beliefs had supported him.

Organization
There is apparently one leader in the organization, specifically the one that argues with Touma just before they attack him and Misaki. There are more than 30 members of the group in the summer of the year before the main story.

It is unknown how someone can join the group other than having the requirement that the person is a student that can no longer advance in the power curriculum program. Because the phenomenon of not being able to advance can affect any student, the people in the organization varies, from high-classed ladies to delinquent boys, as well espers from Level 0 up to Level 4.

Background
It is unknown how long the organization existed but its members have apparently planned and tried to attack Level 5s in the past.

Recent history
Shundou Toshizou, wanting information regarding Shokuhou Misaki's Mental Out ability for the development of the FIVE_Over Modelcase_"MENTAL_OUT", lends to Deadlock Queen Diver suits, knowing full well that Misaki would try to use her powers on them. This is in the hopes of getting data regarding Mental Out when Misaki uses her powers on a Queen Diver user as its helmet has a program that collects data and sends it back to the researchers.

As predicted, Deadlock would later make use of it to attack Misaki. They come upon Kamijou Touma trying to protect her and try to convince him to leave her side, though it doesn't work. After discovering that he is a Level 0, making Touma similar to them, one of the Deadlock members tries to tell him that Misaki may be unconsciously using her Mental Out on him through her AIM Diffusion Fields in order for him to protect her. Realizing that Deadlock sees Misaki for stunting their growth in the Power Curriculum Program, Touma then mocks their thinking, saying that they do not have any evidence and are simply blaming others for their own failures. One of the Deadlock members says that Touma may be being controlled by Misaki as he is risking his for her. Touma says that he doesn't care if he is being controlled as long as he is there being able to help her. Though impressed by Touma's words, they attacked him regardless.

Touma later uses his own body to protect Misaki while she uses her powers on them to have them beat each other. However, this badly injures Touma in the process. When Touma convulses due to the pain, his blood pressure drops to low levels, making it difficult to treat his injuries. What's worse is that giving him anesthetic would lower his blood pressure more and end up killing him. Misaki offers to use her Mental Out powers on Touma as her powers was based on manipulating fluid in the brains. She then uses her powers on Touma to cut off his sense of pain, allowing the EMT present to treat Touma. However, Misaki's manipulation of the fluid in Touma's brain when his blood pressure so low made it so that her ability didn't work properly on him. In the end Touma is saved. However, the pathways to Touma's memories for her have been damaged, preventing Touma from ever remembering Misaki after they meet, a kind of anterograde amnesia.