This reminds me of my two favourite stunts back when I did tabletop gaming.
The first, was in my first real game, playing mostly (though I didn’t know it) with stats people. So, while they’re busy min-maxing, I am building a character with what I see are useful skills to the theif profession. Early on, we’re ambushed and our horsemaster NPC is killed.
DM (smiling evilly): This will need Animal Handling.
(After all, a party full of warriors and palidins and a city-based Rogue won’t dump stats in such a useless skill).
Me: Okay. (I had taken it, because a theif needs to deal with guard dogs, right?)
DM (stares in shock)
I roll and succeed. We keep the horses.
Later on, there’s another battle that we can see coming. The other players start coming up with elaborate plans involving the horses.
Me (repeatedly): You’re not doing that with my horses.
Finally, someone catches on. “What do you mean, your horses?”
Me: I am a theif. They’re mine, now.
Realisation sinks in for the entire party. I am not just here for the traps and locks. If it’s not specifically claimed, it’s mine. And since the others can’t manage the horses…
The second was more of a rookie DM. We reach the giant, scary castle and my Rogue (yes, I like Rogues) was tasked with breaking in.
Me: Okay, first, I am going to do what any semi-competent burglar does.
Table (chorus): Check for traps.
Me (looking at them like they’re clearly not cut out for this): ** raps 3 times on the table rapidly **
DM (caught unawares): Hello?
Me: Hi, I was wondering if we could have a moment of your time. Just take a moment to share the glory of [begins evangelising for some god].
Me (aside to the other players): First rule of B&E. Always check to see if someone is home.
So, a warning to any of you, if we end up playing. My theif will act like one. She’s never just there to help the party open locks.