Merlin’s bow has power and fire enchantments built in and infinity can be smelted in.
- Using the vanilla crafting table, craft a standard Bow
- Continue with the recipe to the right
- Add the Infinity enchantment by smelting the bow in the Brazier.
Just a note, this sucker kills just about everything on the overworld including golems and witches. You can kill creepers and skeletons way before they get in attack range.