Can you play Challenge (an Action) in response to an opponent playing Get Excited during a showdown?

Ruling: No, you cannot play Challenge in response to Get Excited because Challenge is an Action and cannot be played in response to other cards.

Sequence:

• As the player initiating the showdown, you have priority first
• You could play Challenge at that point before your opponent acts
• Once your opponent plays Get Excited, you cannot respond with Challenge