Builder's Hut

A Builder's Hut is the Building where a Builder is located. Each additional Builder's Hut placed summons a new Builder, which is used to upgrade existing buildings or build new ones.

Actions which require a Free Builder

 * Upgrading existing Buildings and building new Buildings (except Builder's Huts).
 * Upgrading the Barbarian King and Archer Queen (the Builder looks like he is upgrading the Altar, though the Hero is actually being upgraded).
 * Placing and upgrading Walls (you only need one Builder free to upgrade multiple walls instantly).