Can you do Pidgeot EX's "Mirror Move" attack if the opponent's last attack "placed damage counters" (as opposed to "doing damage")?
No. Placing damage counters is an effect. Mirror Move does not copy any other types of effects from the last attack either.
Mirror Move
Source: Evolutions FAQ (2016-11-03), TPCi Rules Team (2016-11-03)Nov 3, 2016Compendium → Let's say I have Machop active with a Focus Sash attached, and my opponent's Mewtwo-EX uses "X Ball" for 360 damage with four Double Colorless Energy and a Muscle Band attached. The Focus Sash leaves Machop with 10 HP remaining. If I then use Ninja Boy to switch Machop with Pidgeot-EX and then use its "Mirror Move" attack, does Pidgeot-EX do 360 damage in return?
Yes, it would. When using Ninja Boy the amount of damage done last turn is remembered by the new Pokemon, so Mirror Move would do 360 damage to your opponent's Active Pokemon.
Mirror MoveNinja Boy
Source: TPCi Rules Team (2016-11-03)Nov 3, 2016Compendium →