Minecraft wiki entry for Combat, associated text: Flint and steel is a unique weapon, as players can set a block of fire, and while it burns, any mob that comes into contact with it will catch fire, suffering burn damage over time. This can be very useful when being chased by multiple mobs, as it will weaken all or most of them down to the point where a sword hit or two will be enough to kill them. However, there are several downsides to this method. First of all, mobs may elude the fire by pure luck, requiring another light. Second of all, if the player are in a confined space, circling to avoid mobs, they could potentially set the player on fire by accident. Third, burning mobs can also set themselves on fire when through melee attacks. Lastly, it can take a long time for the mob to die, enough time for more mobs to join the party. A fast player could make a short 1-block netherrack wall and light the top. Mobs would have to jump and they would take damage instantly or over time. Particularly effective with a sword with the Knockback enchantment.