Hammers are tools used for breaking structures. Out of all the tools, they cost the most resources to craft. Hammers are useful because most spears and swords are only able to minimally damage wooden structures. An exception is the amethyst tools, which are capable of destroying any structures, but they do this very slowly. Hammers do significantly more damage to structures. However, there is a trade-off. As aforementioned, the hammers require significantly more materials. As such, looking to get a hammer is only feasible after the player has obtained a generous amount of materials, as well as having the need to use one (raiding, base building).