Righteous Aura

TheInsaniac wrote:

I'm not sure how you're supposed to be able to play Righteous Aura. It's a combat card with the following restriction on playing:

Only usable if this vampire is ready and the opposing minion is not.

But since you have to lock when you declare an action or you block successfully, I don't see how you'll ever be in a situation where this is the case unless someone else's minion enters combat with yours directly. Am I missing something?