Missing Rule?

[Incendax]

I could have sworn I remember reading a rule that states a player knows everything about any powers that are currently effecting her. Did I just make that up in my head, or can someone give me an actual page number for this rule?

Also of importance, does this mean the player knows what effects an attack might have before it hits her, allowing her to make an informed choice about her defensive powers? Alternately, does this mean the player knows any aftereffects that a power might have, allowing her to make an informed choice about effects that grant saving throws?

 

[Gorok]

Page 26-27 of the DMG has an overview on what the players know about and how the DM should inform them. The key phrases from this section are: "Give enough information that the players know what's up and have an idea what to do - and what not to do." and "Describe the ability as it might appear in the game world, and then describe it in game terms to make it clear."

 

[DracoSuave]

They know everything about any effects currently affecting them. This includes 'when I fail this save, this will happen' as that's part of the effect. What it does not include is effects NOT currently effecting them.

However, through visual cues, and through relevant monster knowledge checks, players do have the ability to figure out 'cold zombie radiates cold' or 'Orcus can kill you dead with that thing.'