Shadow13.com wrote:
You can't challenge a house cat or a brick wall because they can't accept your challenge.
The brick wall, sure. A house cat, not so. (Now, unless you're playing Bunnies & Burrows or Mouse Guard or something, you're unlikely to do so.) Animals understand the concept of challenges just fine; just roar at it or move to catch its attention or make yourself look large or something. Animals challenge each other, even.
Challenges should work on anything subject to mind-affecting effects. [/QUOTE
I agree. It is up to the player to issue the challenge in a way that the opponent can understand.