Minecraft wiki entry for Defeating_an_End_city, associated text: Since shulkers and endermen can deal a lot of damage, healing items are absolutely necessary. Golden apples are the most efficient healing item, because they provide Absorption, which will protect you from most damage while you heal, so bring at least 10 of these, also you can find 2 of potions of instant healing in the brewing stand of a end ship, but they are not enough when exploring end cities. Potent healing potions and extended regeneration potions are also required. Enchanted golden apples can heal you more than regular ones, but they are extremely difficult to find, so save them only for emergencies, and use regular golden apples otherwise.