He murdered his father and rose as leader of ShadowClan, taking the name Brokenstar. Under his reign, ShadowClan terrorized the forest, driving out WindClan and sending apprentices under six moons old into battle. Brokenstar was driven out by ThunderClan and ShadowClan, and taken prisoner by ThunderClan. Yellowfang tricked him into eating deathberries to free the forest from his cruelty. In the Dark Forest, Brokenstar helped plan the battle against the Clans and trained living warriors to aid their schemes. He was later killed in the battle by Yellowfang once again.
The exiled rogue and his followers launch an attack on ThunderClan in revenge, but they are defeated and Brokenstar is blinded by Yellowfang. He is kept prisoner in ThunderClan, demoted to Brokentail. The other Clans insist ThunderClan should get rid Brokentail for he is a dangerous cat. This is proven true; even as a blind and injured prisoner, Brokentail plots with Tigerclaw and takes part in a battle when Tigerclaw leads Brokentail's rogues to attack ThunderClan's camp in an attempt to kill Bluestar. Eventually, Brokentail is tricked into eating deathberries by his biological mother, Yellowfang, who reveals her identity to him at last. He doesn't believe her, but loses his last life regardless.
Brokenstar becomes one of the unofficial leaders of the Dark Forest, organizing the Great Battle. He assists Breezepelt in attempting to kill Poppyfrost and Jayfeather, but are driven back by Honeyfern. During this time, he mentors Tigerheart and Blossomfall within the Place of No Stars. He runs into Spottedleaf, Jayfeather, and Yellowfang in the Dark Forest and mocks them as they try to find information about the future conflict. To test Ivypaw's loyalty, he demands her to kill Flametail, who had recently joined StarClan. He continues to doubt Ivypool's commitment, and has her kill Antpelt's spirit. During the Great Battle, he murders Ferncloud while raiding the nursery. Afterwards, Yellowfang kills him a second time and wipes out his existence. After Brokenstar's second death, the Dark Forest cats flee, giving the Clans the victory.
In Yellowfang's Secret, Brokenkit is born to Yellowfang and Raggedpelt, and was named after the bend in his tail, as well as the feeling Yellowfang felt in her heart at the time of his birth. He is the only surviving kit of his litter and is surrendered by his biological mother and fostered by the only queen in the nursery, Lizardstripe. The young kit suffers emotional neglect from Lizardstripe, and is constantly bullied by his foster siblings, Tanglekit, Deerkit, and Runningkit. He is also spoiled by his father, Raggedpelt, who later becomes leader.
He becomes an apprentice and is mentored by Nightpelt, but often refuses to listen to his mentor, who is frail and sickly, and instigates fights with other cats, including those of his own Clan. He is promoted to a warrior, Brokentail, early and becomes the deputy after Cloudpelt dies in battle, despite his young age. He is given his own apprentice, Stumpypaw. Yellowfang finally makes Raggedstar see the truth in their son; his violent and aggressive nature that will ruin the Clan, but Brokentail proceeds to murder his own father to become the leader of ShadowClan, taking the name Brokenstar. He names Blackfoot his deputy. Brokenstar apprentices kits before the age of six moons and forces them to train for battle, such as his own apprentices Mosspaw and Volepaw, and excludes elders from the "safety" of the camp. He exiles his biological mother, Yellowfang, after accusing her of killing Marigoldkit and Mintkit, most likely because he saw her as a threat to his reign as well.
I am proud of my Clan. You are all I could have hoped for as a leader. With warriors like these, I could fight any battle! And there will be a new warrior today. Brokenpaw, step forward.
Raggedstar, Brokenpaw hasn't completed his final assessments yet.
I know a cat who is ready to be a warrior when I see one. I, Raggedstar, call upon my warrior ancestors to look down on this apprentice. He has trained hard to understand the ways of your noble code, and I commend him to you as a warrior in his turn. Brokenpaw, do you promise to uphold the warrior code, to protect and defend this Clan, even at the cost of your own life?
Then by the powers of StarClan, I give you your warrior name. Brokenpaw, from this moment you will be known as Brokentail - but let no cat see this as a sign of weakness. You are one of the strongest cats I have ever known, and I look forward to fighting alongside you! StarClan honors your courage and your fighting skills, and we welcome you as a full warrior of ShadowClan.
Cats of ShadowClan! We have lost Cloudpelt and we grieve for him. But the life of the Clan must continue. It is time to appoint a new deputy. I say these words before the body of Cloudpelt, and in the presence of the spirits of my ancestors, that they may hear and approve my choice. Brokentail will be the new deputy of ShadowClan. True, Brokentail is still younger than most of you, but ShadowClan has never had a braver or more skillful warrior. He is an example to us all, and it will be a great honor to lead the Clan with him.
I give you a life to live by the warrior code. Remember it well, Brokentail, and let it be your guide. Wiser cats than you or I have lost their way without it.
I give you a life for duty. Remember what you owe your Clan as well as what your Clan owes to you.
I give you a life for honor. Honor is expected from all cats, but most of all, from a Clan leader. Use the honor of leadership carefully.
Skinny gray tom:
I give you a life for truth. Without it, kin is set against kin, Clan against Clan. Hold fast to truth in all your dealings and let it guide your words.
I give you a life for judgement. ShadowClan stands at a place where the path ahead divides. choose to follow the right path, for the good of your Clan.
I give you the life for love of kin. And as a Clan leader, remember that every Clan cat is your kin.
Small brown tabby she-cat:
I give you a life for clear sight. Brokentail, know yourself and your destiny, but know too that destiny can be changed if you choose the right path.
Plump black-and-white tom:
I give you a life for strength. This is the time you and your Clan will stand or fall. You need to be stronger than ever.
Brokentail, I give you a life for compassion. Use it to shelter the weakest in your Clan, the kits and the elders and the sick. Use it to show mercy to your enemies and to choose the path your paw steps will follow.
"I've come to tell you not to waste your efforts with Cloudpelt. His time is over. He would never have been able to lead ShadowClan. There is only one cat who can do that after Raggedstar. I will be the next leader of ShadowClan."
—Brokentail when Yellowfang is attemping to treat Cloudpelt's wound Yellowfang's Secret, page 413
"Those kits were weak. They would have been no use to ShadowClan. If I hadn't killed them, some other warrior would have."