Diego Aiza

Diego Aiza is a supporting character introduced in Season 6 of The Boy from the Bunker, and is portrayed by Isaiah Mustafa in the books. He is the leader and succeeding King of Blood Riders who independently steps up on his own accord to take charge of Blood Riders when all three kings in line are killed (Rogue Rule, Noah Rule, and Jonas Rule).

Diego's family is not referenced in the books, but he is the King of Blood Riders and thus, has a large clan of people he is responsible for. He forms an alliance with the Sovereigns of Basilisk - Dreea Taven, Kodiak Zora, Wynn Bell and, despite a rough start to their friendship, he ends up forming a bond with Elara Bell Zora.

 Season 6 

It is revealed that after all three Kings (and next-in-line) are killed - Rogue Rule, Noah Rule, and Jonas Rule, Isaiah takes initiative in his leaderless clan and appoints himself as King when he realises the growing conflict between Basilisk and The City of Targo who are both nearby to Blood Riders' camp. When majority of Blood Riders leave with The City of Targo upon a deal that grants them better living conditions in The City, Diego remains behind with a small percentage of his people to rebuild Blood Riders camp which is still damaged from the fire in Season 3. When he asked by the Sovereigns of Basilisk to meet, Diego heads out with his second, Nathaniel - to listen to them. He is surprised when they ask to form an alliance given that Basilisk and Blood Riders have been each other's longest lasting enemies since their clans began however, he listens to their deal nonetheless. When Sovereign Wynn's siblings - Quill and Elara appear out from nowhere, Diego begins to suspect that have been tricked into meeting with them so that the Sovereigns could kill them but, he quickly realises that Sovereign Kodiak and Sovereign Wynn are just, if not more, shocked than he is to see them there. Stunning everyone, Elara takes lead of the conversation (much to Kodiak and Wynn's alarm) and manages to persuade Diego into accepting the alliance. However, when Diego leaves to head back to Blood Riders with Nathaniel, he is knocked unconscious and soon wakes up to the group from Basilisk surrounding him. Unable to remember what happened, Diego assumes the people of Basilisk did something to him and grabs onto the nearest person possible and pulls them into a headlock - which just so happens to be Elara. As the group panic at the sight of Elara being hurt by Diego, they hurry to assure him that they weren't the ones to attack him and that it was Nathaniel - who tried to do the same to them moments ago, but they killed him out of self-defence. When Diego realises they are telling the truth, he lets go of Elara and suddenly worries that he has done too much damage, but she pulls through. Despite a rough start to their alliance, both Diego and the Sovereigns understand that it is the best option to continue with it as both clans have a lot to gain from the alliance. Days later, Diego and the rest of Blood Riders temporarily move into Basilisk's camp as an act of securing trust with each other. Diego leaves behind the elderly, children, and those incapable of fighting at Basilisk whilst he and the stronger, healthier members of Blood Riders join the Sovereigns and their team to cross the DeadLands and head to The City of Targo. Once they make it through the DeadLands, Diego and Blood Riders stay with Basilisk at the refuge located a few miles outside of The City. Diego works closely with the Sovereigns in their entry into The City and efforts to rescue Sol and the group of Blood Riders also inside. When their planned riot takes place within The City, Diego offers protection to Elara and Quill as they enter inside to find their brother in a way of earning redemption for how he had previously hurt her. Once Sol and his people are out of The City, they travel back together through the DeadLands and return to their own clans.