Without more details about the 'black halo story', it's impossible to determine the main characters. However, if it's a typical hero - villain type of story, the main character could be someone who is either trying to obtain the black halo for good or bad reasons, and there might be an antagonist who is trying to stop them or use the black halo for their own evil purposes.
Since I don't know the exact 'black halo story', I can't say who the main characters are.
Given the lack of information, the main characters could range from a young and naive character who discovers the black halo and is thrust into an adventure because of it. There could be a group of adventurers who encounter a being with a black halo and have to decide whether to befriend or fight it. And there might be a shadowy figure in the background who is somehow controlling or influencing the black halo's existence in the story.
In the 'Epica Black Halo story', there may be a hero - like figure who is the central character. This character could be on a quest to overcome some sort of darkness or chaos. There might also be a powerful, malevolent force as an opposing character. However, the exact nature of these characters is somewhat open to interpretation as the story is told through music and lyrics which can be quite abstract at times.
In 'halo the story', the main characters include Master Chief, a highly skilled and powerful Spartan - II. Cortana, an AI, is also very important as she assists Master Chief in many ways. There are also various Covenant leaders who play significant roles in the story, like the Prophets.
The main characters are Master Chief and Spartan Locke. Master Chief is the iconic hero of the Halo series, and Locke is the one sent to find him.
The main characters are Master Chief and Cortana. Master Chief is the super - soldier who does most of the fighting, and Cortana is his AI sidekick who provides support and knowledge.
Since we don't know the specific 'dark halo story', it's impossible to say who the main characters are.
The main characters are the Master Chief and the Arbiter. The Master Chief is a Spartan, a super - soldier for the humans. He's very skilled in combat. The Arbiter is an elite Covenant warrior who gets caught up in the Covenant's internal power struggles.
The main character is Master Chief. Cortana also plays a very important role. She is an AI who assists Master Chief throughout the story. And, of course, there is the Didact, the main antagonist in the Halo 4 game story.
Since we don't have much information, it could be Master Chief and Cortana in a different, more romantic light. They have a deep connection in the Halo series already, so it's possible they could be the main characters in a love story interpretation.
I don't know yet as details about the 'new halo story' might not be fully released. But it could include Master Chief as he is a staple of the Halo series.