Wild Cat

A stranger walks into a saloon and gets a drink. He sees a poker game and asks if he can play. He's told to take a seat. It's a no limit 5-card draw game and he's a pretty good player. After about an hour of so-so hands, he draws Aces full and makes a sizable bet. The old guy across from him raises all-in and the stranger calls. The old guy lays down 23457o and reaches for the chips.
"Whoa, there. I've got Aces-full."
"Yeah, but I've got a wild cat.", says the old guy.
"A wild cat? What the hell is a wild cat?"
"A wild cat is 23457 off-suit." Like this, "Says the old man."
The stranger starts to burn and says, "I've played a lot of poker, but I've never heard of a wild cat."
"Well, if you've played a lot of poker, you oughta know that you should learn the house rules before you play. And this here's a house rule."
At that,the old guy points to a sign just over the stranger's right shoulder. The sign says,
"House Rule - Wild Cat is a 23457 off-suit and it beats everything"
Being a gentleman and an honorable gambler, the stranger takes his lumps and settles back for more poker.

Several hours later, the stranger is dealt 23457o. He bets and the same old guy raises him the pot. Without the slightest hint of a tell, the stranger raises all-in. The old guy calls and lays down an ace high flush, and reaches for the chips.

"Whoa there! I've got a wild cat.", says the stranger as he lays down his cards.
"Nice hand.", says the old guy as he scoops up the pot. "What did I tell you about house rules?", as he points to a sign over the stranger's left shoulder.
"House Rule -Wild Cat - Only Good Once a Night"