Missile is one of the Rocket Brothers, lead by his big brother Rocket.
Missile has notably darker fur color than his brothers.
Missile is less rightful and hopeful than his big brother, strongly believing that the strongest will always rule.
After Jet got killed, Missile confidently attacked Hōgen, but was easily defeated.
Ginga Densetsu Weed
As Missile as his brothers get the task to capture Weed, Rocket joins the group as a spy. When Rocket sees his chance, he grabs Weed and runs off to his brothers, so they can take him to Hōgen.
Jerome leaps in, and manages to give the brothers a fair fight before the rest of the pack shows up. Weed decides to spare them, which makes Rocket leave his brothers to join Weed. Misslie and Jet go back to Hōgen, where they are killed as punishment for their brother leaving the pack.
In the manga, Missile, Jet and Rocket were not Hōgen's minions but as guests. After having a feast of deer meat as presented by Hōgen, he and his brothers were given a task - to capture Weed. On their way, they bumped onto the blind Ben and the old Saluki, Cross. Fortunately, the Borzoi Brothers did not harm them and went on with their duty.
After Missile succeeded in snatching Weed off from his pack, the brothers were deciding what to do with the puppy when Jet tried to attack Weed but was stopped by Jerome who showed up just in time. The Borzoi Brothers fought Jerome until Weed's pack interrupted it that they ran away empty-handed.
However, Rocket decided to join the Ohu Soldiers from realizing his true purpose from Saburō's words and left his brothers behind. Shortly after that, Missile and Jet returned to Hōgen only to be killed by Hōgen and his minions (Jet was killed by Hōgen's minion, then Missile was killed by Hōgen himself).
See more pictures in Missile/Gallery.