This came up today, Kabalite Strike Force attacked using it's AoE ability. Tau had a Fire Warrior Elite and about 6 more units in play. If I understand it correctly, AoE is an effect and would mean that there isn't a specific unit chosen as the target? Therefore it would not trigger FWE's effect to soak up damage? This is how it was played, though I triggered Repulsor Impact Field, which I now understand to be incorrect.

Correct (now) on both accounts.

then definition of Area Effect on p.3 of the RRG clarifies that Area Effects replace the attack against a chosen defender with general effect damage assigned to each enemy unit at the planet. Since there is no attack declared against one of your units, the triggering condition for Fire Warrior Elite's interrupt is not created and so it cannot be used. Area Effects are also not considered to be attack damage, so Repulsor Impact Field's triggering condition is not created, either.

Thanks! I did read the RRG, but I couldn't understand what replacing with AoE would mean, as far as choosing defenders. So, I went with what made most sense based on what I knew of it. I'm a little embarrassed, because I should've known better with Repulsor Impact Field.

As an aside, it seems that most misplays have come when Tau are involved. Wonder if this is just me, or their effects, generally speaking, create more unusual situations.

Not just you. Tau definitely have the most complicated interactions in the game. It might be worthwhile checking out the TAU attachments tutorial in the cardgamedb rules forum, plus there's some useful threads on Repulsor Impact Field that might cover stuff you haven't seen yet.

Thanks! I will do so.

Remember that shield cards can still be used during AoE (rules reference guide pages 6 and 14). We had some confusion about this early on, thinking it was only when you were delcared the defende!

Shields can be used for any damage unless it specifies otherwise or involves Armorbane.