He is seen preparing WindClan for a battle against ShadowClan. The two Clans meet at the border. Blizzardstar, an ancient ShadowClan leader, antagonizes Hazelstar, remarking on how small some of the apprentices are. Hazelstar is about to lead WindClan to attack, but the queens, Daisytail of WindClan, Hawkfoot of WindClan, and Oakleaf of ShadowClan stop them. They propose that all apprentices should be six moons old in order to fight in a battle; that way the Clans won't lose any warriors, and the apprentices have enough time to train.
When Hazelstar is asked if he will go through with this, he replies that it would be unwise to lose the future of their Clan, if he let them grow older, battles would be more easily won. It is said he makes it sound as a threat instead of a weakness. The two propose it as a law at the next Gathering, and the other leaders agree, and so, the rule goes into affect as the fifth law of the Warrior Code: kits must be six moons old before they begin apprentice training.
"Warriors of WindClan! And apprentices! ShadowClan has stolen from us one too many times! We will teach them that WindClan's borders are strong, they will be defended with claw and tooth, and our prey protected for our Clan alone."