I usually like to give little bits and pieces of information to the group to get them excited about the upcoming session, but nothing that could be considered spoilers, something like:
I had a bunch of time to work on a couple of new NPCs, I think you'll like them
That has been working very well, the group looks forward to the next session and I can usually deliver on the content I promised, but there is a problem.
There is a player in my game who keeps asking questions about the next sessions and secret lore in general, things like:
- So, what god will I be able to meet soon?
- Can I have the rulebook for a second? I have to check out the creatures and gods sections.
- I sure hope I get to meet a powerful mage in the next session.
I like to keep an air of mystery about the adventure, so the fact that he keeps reading the GM section of the rulebook (which contains monsters and gods, and all their rules and stats) and pointing out things like "oh, finally I know what that encounter was!" bothers me.
I tried telling him that he can't see the rulebook and that I can't tell him anything that would spoil the adventure, so that he would enjoy it more. But he insists on talking about the adventure outside of the sessions, and it doesn't help that I have a hard time telling people "No", and the fact that I'd like to accommodate everyone.
I also considered the option of telling him fake information about the adventure so that he won't spoil any surprises, but that still won't help with his obsession about the rulebook.
How can I (politely possibly) tell him that his behaviour is not helping the "natural" flow of the adventure?
The other players already know that and usually keep quiet about the adventure in between sessions, so they aren't a problem.
I would also like to keep him in the group as it is very small and there aren't many RPG enthusiasts in my area.
The player in question has been playing tabletops RPGs for about 2 years, so he's experienced. He also GMs some campaigns; he tends to give out a lot of information about his campaigns too, if that helps.