I'm going to start out by saying that I am fairly new to D&D, but I am constantly reading material to better understand the game. My GM and I were having a discussion about reach weapons and we came to a disagreement on how the rules work on attacks of opportunity.
Im not 100% sure that this how it works but in all of the material that I've read it leads me to this conclusion.
If I'm playing a human and I am wielding a weapon that has reach I threaten the tiles at 10 feet and not the tiles at 5 feet.
Now where we come to the disagreement is, if an enemy is moving through my threatened area at 10' and moving to 5' to engage me in melee, I believe that I would get an attack of opportunity. He says that I wouldn't because they aren't taking their attention off of me or otherwise dropping their guard. I pointed out the rules where it says that if they move out of my threatened area I get an AOO, but he still didn't agree with it.
I then tried to explain it with practical reasoning by saying, in real combat if I was holding a spear and someone was running at me with a sword I would have plenty of time to get a stab in on them. You assess combat differently if you can attack at a distance and this give you more time to react to things around you.
Thanks in advance to anyone who can clear this up for me.
