How does "Attack Of Opportunity" work?

Hello everyone.
I am making a computer game on the UNITY engine, at the moment it is a TOEE clone, but I plan to make the locations and the plot different. Working title "Palace of Chaotic Good". I often have trouble with D&D rules. Some parts of the book are poorly written. I'm interested in how "Attack Of Opportunity" works in TOEE.

1. The character crosses the enemy zone (Triggered).
2. The character enters the enemy zone (Does not work).
3. The character leaves the enemy zone (Triggered).
4. The character is in the enemy zone, starts moving in the enemy zone, moves in the enemy zone and ends the movement in the enemy zone. (???)

If two weapons are in hand, does the character hit with two or one?

I don't know English, that's why this style of writing.

 

If the enemy has a reach/and/or a reach weapon they should get one aoa as you approach.
using an unarmed attack without the improved unarmed attack provokes an aoa.
Using a 5ft move does NOT cause an aoa(could apply to #4 above)
You get One aoa per turn unless you have Combat Reflexes then you get as many aoa as your dex bonus(min 1)
Using Spring Attack feat does not give aoa
If a creature is right in front of you and tries to move around you unless they make a successful acrobatics role you get an aoa (applies to #4)
So, If say 5 creatures try to run past you(or up to you if you have reach) you get one aoa unless you have combat reflexes (say dex 16) then you would get one aoa against each of the first three (also see the acrobatics skill)

 

Opportunist (Rogue talent) modifies AoOs.

Various other abilities also modify AoOs.

 

Nothing is clear. You write like a book.

The characters are medium in size and are armed with swords. The first character to approach to strike. Will the second character attempt to strike before the first character strikes? Is it in the DnD rules? Was it like that in "The Temple of Elemental Evil"?

Taken from here https://www.d20srd.org/srd/combat/attacksOfOpportunity.htm

It turns out that you can walk in the enemy zone and you can enter the zone. But leaving the zone is punishable. Is this true? Now I'm only interested in movement and characters of the first level. This is the hardest one.

@Endarire Thanks for the link, I didn't know about this site.

If a character has a weapon in each hand, does he hit with two weapons or one?

 

Normally, AoOs are only made with one weapon. if wielding multiple weapons, the AoO maker can choose which weapon to use which is normally in their main hand. Hydras are an exception to this, in that they can make an AoO per head.

 

That's what I did.

Spoiler

Now my AoO works for leaving the zone only. I would like to clarify, for entering the enemy zone and moving in the enemy zone, the AoO works?
When the AoO is triggered, the character turns towards the enemy. Then the character turns back? So you can turn your back on a thief. I have characters rotate into place after AoO is triggered. How will it be right?

 

I noticed that in TOEE AoO does not work when changing weapons.