In what order do attacker and defender abilities resolve during a showdown, and how do layers interact with this timing?

Ruling: When a showdown occurs, "when you defend" triggers go on the chain after "when you attack" triggers, meaning defender abilities resolve first, then attacker abilities resolve. Layers do not affect this timing.

Sequence:

• The defending player's triggers (Ahri's ability and Fortified Position) go on the chain in whatever order that player chooses
• The attacking player's triggers (Yasuo's ability) go on the chain after
• The chain resolves in reverse order: Yasuo's ability resolves first, then the defender's abilities
• Wait, correction: "When you attack" triggers go on the chain BEFORE "when you defend" triggers
• This means defender triggers resolve first (last in, first out)
• So: Ahri gives Yasuo -1 Might, then Fortified Position gives Shield 2, then Yasuo deals damage

Nuances:

• The defending player can choose the order for their multiple triggers (Ahri and Fortified Position)
• Layers (trait altering, ability altering, arithmetic) are separate from trigger timing and don't affect when abilities go on the chain