Brambleclaw does kill someone. He killed Hawkfrost because hawkfrost tries to take over the forest.
He and Brambleclaw were with Firestar, who was stuck in a fox trap, and Hawkfrost told Brambleclaw to tighten the trap and kill Firestar, but Brambleclaw killed Hawkfrost instead, fulfilling the prophecy "Before there is peace, blood will spill blood, and the lake will run red."
No, but he tries to kill Hollyleaf, Jayfeather, and Lionblaze because he thought that if Squirrelflight watched her kits die then she would go to Ashfur. But Hollyleaf, Jayfeather, and Lionblaze are not Squirrelflight and Brambleclaw's kits.
He dies when Firestar gets stuck in a fox trap and he wants Brambleclaw to kill Firestar so he can be leader. Brambleclaw reacts to his leader instead. Next, Hawkfrost threatens to kill Brambleclaw. He thinks quickly and shakes up the pole from the fox trap. Letting this get tamperd, he grabs the sharp pole and right when Hawkfrost pounces, she nails it right into Hawkfrost's throat.
There is much spectulation on how Firestar will die, and on a fan chat, the Erins say that he will probably die in the last book of Omen of the Stars. But Brambleclaw will not succeed Firestar.
He got his throat slit by his brother. Hawkfrost attacked Brambleclaw and he is pierced in the neck by the stick from the fox trap. Brambleclaw, his Half-brother, never meant to kill him.
*Spoiler Alert* No Hollyleaf does.
I think it will be Lionblaze. I hope not because I hate Lionblaze! I wish Lionblaze did everything Hollyleaf did and Hollyleaf was still alive to be the next leader. Lionblaze is a betrayer to his Clan! Kill Lionblaze! I like Brambleclaw. I want Brambleclaw, Graystripe, Brackenfur or Cinderheart to become leader.
Brambleclaw kills his half-brother, Hawkfrost, in self-defense during a battle. Hawkfrost had betrayed ThunderClan and threatened Brambleclaw's life, forcing Brambleclaw to kill him to protect himself and his clanmates.
He kills him by using a part of the fox trap that was supposed to kill Firestar
Ashfur was the cat who helped Hawkfrost try to kill Firestar in the last book in The New Prophecy Series, Sunset. In the fifth book in The Power of Three Series, Long Shadows, Ashfur reveals himself to Squirrelflight, Jayfeather, Hollyleaf, and Lionblaze as the one who attempted the murder. He was furious at Squirrelflight and wanted her to feel the pain of losing a loved one like he when she left him to be with Brambleclaw.
Some people don't like Brambleclaw because of his relationship to Tigerstar and because he was tempted to kill Firestar. However, Brambleclaw did prove his loyalty when he killed Hawkfrost to save Firestar.
Haawkfrost died when Brambleclaw stabbed him in the stomach with a stick. This was when Hawkfrost trapped Firestar in a fox trap and was about to kill him when Brambleclaw stuck with loyalty and turned on Hawkfrost.