I never really looked at what the reach weapon property does because I assumed it was the same as it always has been, but it isn't. For some reason or another, it was changed for A5e to this:
Reach. This weapon can be used to make attacks against targets within 10 feet. If a weapon has a longer reach, it is stated in parentheses after this property.
In O5e, and I think in every edition prior (don't quote me on that), it does this:
Reach. This weapon adds 5 feet to your reach when you attack with it, as well as when determining your reach for opportunity attacks with it.
Notice that in A5e, it rather specifically does not say that it increases your reach but just that you can make attacks against targets within 10 feet. This is important because it really makes reach weapons unattractive in ways that I have trouble believing were intended, but then I don't know why they bothered to change the wording at all when it was already quite clear (a rarity for o5e). Here's what I mean:
Reach. This weapon can be used to make attacks against targets within 10 feet. If a weapon has a longer reach, it is stated in parentheses after this property.
In O5e, and I think in every edition prior (don't quote me on that), it does this:
Reach. This weapon adds 5 feet to your reach when you attack with it, as well as when determining your reach for opportunity attacks with it.
Notice that in A5e, it rather specifically does not say that it increases your reach but just that you can make attacks against targets within 10 feet. This is important because it really makes reach weapons unattractive in ways that I have trouble believing were intended, but then I don't know why they bothered to change the wording at all when it was already quite clear (a rarity for o5e). Here's what I mean:
- "You can use your reaction to attempt an opportunity attack when a hostile creature that you can see moves out of your reach." Because your reach is not increased, you still only threaten the 5-foot area around you. This is a huge change from o5e and really kills the point of reach weapons for many people, especially when...
- The Polearm Savant feat's only reason for having anything to do with polearms is just that it requires you to wield them. You no longer threaten out to 10 feet, so the idea of making an opportunity attack when creature's enter your threatened space really has nothing to do with polearms.
- The Shoulder Check maneuver is one of the few things that benefit from this wording, I think, as it seems silly to shoulder check someone 10 feet away. But it does specify "within your reach," so using the o5e reach property would allow you to do so.
- Any monster that already has a longer natural reach than 10 feet, if there are any, that then wields a halberd would actually lose range when attacking with it. The property does not say you can attack 10 feet farther away than normal, just that you can attack targets within 10 feet.