Should be careful not to just shut down player ideas. If everything they do slams into an annoying problem, it can quickly stop being fun.
I sometimes try to sync with the players and be like “hm do you think the 300 year old vampire has had to engage with the city before? What sort of plans and influence do you think he has?”. Then it doesn’t feel like I’m just screwing them, if they’re thinking about it too.




I usually ask the players something like “if it was this easy, why doesn’t everyone else do it?”. Sometimes they’ll dismantle their own ideas given the prompt.
Or, sometimes I’ll say “are you sure you want NPCs to use this tactic?”