Minecraft wiki entry for Experience_farming, associated text: Fishing with any rod will eventually catch enchanted fishing rods, which can be saved until a rod with Mending is caught. This rod can be combined (at an anvil) with other rods as they are caught; once Mending is combined with Unbreaking, this rod will never wear out, and fishing becomes essentially free. The goal is to produce a "god rod", with (Lure III, Unbreaking III, Mending, and ideally Luck of The Sea III), which maximizes both fishing speed and treasure gained, while minimizing the experience used to restore the rod.