Minecraft wiki entry for Defense, associated text: • If you have a lot of iron ingots and pumpkins, then you can make the perfect defense. Iron golems have 50 hearts and can kill most mobs in 1-2 hits. Make sure to keep them near your house though; as they may wander away. To prevent this, put the iron golems inside of a trench surrounding your house. The trench should be 2 wide and at least 4 deep, otherwise the golems will fling mobs back out of the trench. An alternative is to leash them to a fence using leads.