Reach and Threatened Squares

Your reach is the distance at which you can attack foes in melee combat. If you are wielding a melee weapon or are otherwise capable of making a melee attack (e.g., if you have your own natural weapons), you threaten all squares into which you can make a melee attack, even when it is not your turn (the exception is unarmed strikes—if you’re making unarmed strikes, you don’t threaten other squares). Generally, that means you threaten all squares adjacent to your space, including diagonally. An enemy that takes certain actions while in a square you threaten provokes an attack of opportunity from you (see page 248).

A creature’s natural reach refers to its reach in melee combat when it is not wielding a weapon with the reach special property. Small and Medium creatures have a natural reach of 5 feet. When wielding a weapon with the reach special property, you threaten all squares that you can reach with your weapon. This typically extends a Small or Medium creature’s reach to 10 feet. For more about the reach weapon special property, see page 182 in Chapter 7.

Creatures that take up less than 1 square of space typically have a natural reach of 0 feet, meaning they can’t reach into adjacent squares unless using weapons with the reach special property. They must enter an opponent’s square to attack in melee. This movement may provoke an attack of opportunity from the opponent. You can attack into your own square if you need to, so you can attack such creatures normally. Since they have no natural reach, they do not threaten the squares around them. You can thus move past them without provoking attacks of opportunity, and they also can’t flank enemies.

Creatures that take up more than 1 square of space typically have a natural reach of 10 feet or more. Such a creature usually can make an attack of opportunity against you if you approach it, because you must enter and move within the range of its reach before you can attack it. You do not provoke this attack of opportunity if you take a guarded step to approach it. When wielding a weapon with the reach special property, such creatures extend their reach by 5 feet.

If your reach is 10 feet, you threaten the second square of a diagonal (this is an exception to the normal rule for calculating distance along a diagonal; see Diagonals on page 256 for more information). If your reach is anything other than 10 feet, calculate the diagonal distance of your reach normally.