If dropping the mobs to kill later, make an opening showing just their feet so they can't attack you.Bubble columns are useful when getting the mobs up high enough to drop.You may want to dig the pit deeper than the required 19 blocks in case a spider does brush the wall at some point in its descent. To kill spiders, a minimum of a 2×2 pit is necessary. Spiders can be tricky to deal with as they can grab the walls and reduce fall damage. However, stone swords are cheap and plentiful, and you can also use tools (such as shovels) dropped by the zombies. If you wish to use your fist rather than a tool to kill the mobs, a strength beacon may provide the extra damage necessary to kill zombies and mobs with armor in a single hit. In Java Edition, it is not possible to bring zombies to half a heart, even with a combination of falling and suffocation, because zombies have 2 ( ) natural armor points. By dropping the mobs slightly lower than the minimum death height, it possible to make most mobs end up with 1 health points, so you can kill them with one hit. On the other hand, it is often desirable to kill the mobs manually in order to obtain experience and other exclusive drops. Because of this, it is often better to make the drop further than necessary. Some mobs such as zombies and skeletons can occasionally spawn with Feather Falling boots or armor that can change the required distance. Most common hostile mobs can be killed with a 24-block drop, although witches require 30 blocks. Different mobs need to be dropped different distances in order to kill them. The most important aspect of a fall damage grinder is the drop height. These include iron golems, chickens, cats, and flying mobs such as blazes. This method is often done in combination with a mob farm where the mobs are forced into water streams and can easily be dropped from a lethal height. Fall damage is one of the simplest and quickest methods of mob grinding.