Not sure if this is a bug or not but I played sundering strike on an opponent with armor of faith and the 3 damage was still prevented and the trait was removed. I had expected since the trait has the armor keyword, it should be ignored and removed by sundering strike I'm sure it being a trait instead of a card in hand is the root cause.
I'm pretty sure Stone Feet isn't removed by armor removal either, but essentially like you said I just took it as a non-in-hand armor doesn't count type of thing.
You can only remove attachments applying armor effects via the usual attachment-removal tools. That much has always been true, this is not a bug. Basically Sundering Strike only makes the opponent cards which are of type Armor (grey cards). Armor Of Faith (just like Stone Feet) is of type Assist. The attachment applies an armor effect, but it's not an armor card in itself. I reckon the wording on Sundering Strike might be misleading, but I also can't think of an alternative wording which would explain the difference w/o bloating the card text excessively. Unless the devs think armor removal should affect attachments too, this will probably stay as one of many Gotcha! Rules.
Haha, card type, duh! Thanks Bandreus, just when you think you know the game, you realize you're still forgetting little things!
