1. If I use Meera Reed to blank an attachment on something other than a character, like Increased Levy, the attachment falls off, correct? So what happens when I use her to blank a chamber that's been attached to a house card as an attachment (like Aeron's Chambers)?

2. There's been a few discussions on this and I would just like some clarification, please. Can Meera Reed blank The Red Viper (PotS)? Can Meera Reed's blanking ability be cancelled by The Iron Throne (LotR)?

3. Am I the only one who thinks that Meera Reed's interaction with the game is confusing as hell?

1. The "You may choose to play (Chambers) as an attachment to your House card." text functions the same as "attach to your House card." Blanking the text makes the attachment illegal, and so it is discarded.

2. The answer to both questions is "No." Your chance to cancel Meera is before she enters play, so she is an effect, not an ability, at that point. No "cancel an ability" effects allowed. However, the "then blank..." part of her text does not initiate until she is fully in play, making that part count as an ability. So "immune to character abilities" blocks her blanking. And yes, that means that the nature of her triggered text changes over the course of its resolution.

3. No, probably not. But it has less to do with Meera per se and more to do with the fact that "then" effects essentially initiate twice.