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.
Because Hawkfrost set a trap for Firestar so Brambleclaw could become the leader of thunderclan. but he didn't want his leader to die that way so he killed Hawkfrost to save Firestar.
Hawkfrost died when he was killed by Brambleclaw during a battle near the end of the book series 'Warriors' by Erin Hunter. Brambleclaw defended his clanmate Firestar against Hawkfrost's attempt to harm him, leading to their intense fight where Hawkfrost ultimately met his demise.
Brambleclaw does kill someone. He killed Hawkfrost because hawkfrost tries to take over the forest.
*Spoiler Alert* No Hollyleaf does.
He kills him by using a part of the fox trap that was supposed to kill Firestar
Midnight, the first book in the Warriors: The New Prophecy series, features a depiction of the cat Brambleclaw on its cover, standing in a forest with glowing yellow eyes.
Sorry there is no Hawkhead is the warriors series, there is Hawkfrost (Brambleclaw's half-brother and Mothwing's of Riverclan brother.)
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.
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.
Goldenflower. He is the half-brother to Brambleclaw and Tawnypelt. Goldenflower had a unknown tom as her mate and gave birth to Swiftpaw. Then, Goldenflower had another mate, Tigerstar. She gave birth to Brambleclaw and Tawnypelt. Brambleclaw, Tawnypelt, and Swiftpaw shared same mother, but had different fathers.
Yes, in the Warriors series, Ashfur becomes consumed by jealousy when Squirrelflight reveals she doesn't love him and loves Brambleclaw instead. This leads Ashfur to plot against Brambleclaw and attempt to kill him in various ways in his attempt to get revenge.
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."