Starclan cats give their own lives to new leaders during their nine lives ceremony. With each life lost, the cat that corresponds to that life returns to an area of Starclan designated for them and the other life givers. Here they meet with the leader to heal them and talk to them when they lose a life. 

After his encounter with Scourge, each cat that gave Tigerstar a life appears one after another, but are unable to heal him. He’s forced to watch as each of his lives appear in front of him, until there are none left.