When an Attack of Opportunity Provokes an Attack of Opportunity
In some cases, you can make an attack of opportunity that provokes an attack of opportunity against you. For example, a foe runs past you, leaving a square you threaten and provoking an attack of opportunity from you. If you choose to disarm your foe, you'll provoke an opportunity from that foe (unless you're out of the foe's reach).
Attack of Opportunity Chains: If both you and your foe have multiple attacks of opportunity, the two of you could set up a whole chain of attacks of opportunity. For example, you try to disarm, provoking an attack of opportunity. Your foe responds by attempting to disarm you, and you respond with another disarm attempt.
When this situation occurs, simply allow both foes to keep going with attacks of opportunity until one of them either runs out of attacks of opportunity or chooses not to make any more. Keep track of all the attacks of opportunity each combatant provokes and makes. Resolve the final attack of opportunity in the chain first, and then work forward along the chain until you've resolved all of them or until one opponent's attack of opportunity foils the other's action.
Let's return to our previous example: Let's say you have three attacks of opportunity available and your foe has two.
You make a disarm attempt when your opponent moves past you (attack of opportunity #1). This provokes an attack of opportunity from your foe.
Your foe decides to disarm you in turn (attack of opportunity #2). This provokes an attack of opportunity from you.
You decide to disarm again (attack of opportunity #3).
Your foe also decides to disarm again (attack of opportunity #4 and your foe's second and last attack of opportunity).
You decide to disarm yet again (attack of opportunity #5 and your third and last attack of opportunity).
Your foe would like to disarm you again, but he's out of attacks of opportunity, so that's the end of the chain.
Resolve attack of opportunity #5 first; if you succeed, your foe no longer threatens you and can't continue, bringing the whole process to an end. If you fail to disarm your foe, move on to attack of opportunity #4; now your foe has a chance to end the process by disarming you. Continue until one of you is disarmed or until all the attacks of opportunity are resolved.
