The language for the card, Frozen Moat says:
Challenges: Kneel Frozen Moat to choose 1 attacking character. Until the end of the challenge, treat that character as if its printed text box were blank.
Hodor says: Deadly. No attachments.
Hodor cannot be declared as an attacker. Hodor cannot be bypassed with stealth.
Here is the question: If I am the attacking and active player, the active player declares challenge type and opponent. Now, before active player kneels attacking characters...Can I use Frozen Moat to blank Hodor?
OR can I use it in the player action window before the challenge even started (the effect lasts "until the end of the challenge")? A sort of preemptive blanking. I am the attacking active player, and the Frozen Moat doesn't specify that the character be participating in a challenge, just that it be an attacking character. Aren't all characters I control "attacking characters" since I am the active player?
Basically, I wanted to use Hodor to attack, can it be done in this manner?