Concealment, Cover, Invisible

[fafhrd]

Standing behind a low wall: cover, no concealment
Standing in a fog bank: no cover, concealment
Standing behind a low wall in a fog bank: cover, concealment

 

[Sammael]

I've been using Conceal 5 and 11 in my games for about three years now. It seemed natural at the time, as I was making an effort to eliminate d% from my 3.x games.

 

[Andur]

Standing behind a tall wall, cover and concealment, but without the chance of being targetted at all...

Upturned table I'd treat the same as whatever the largest shield in the game would grant. A shield grants cover, but I don't think you'd find many who would say it provides concealment.

 

[fafhrd]

EDIT: made no sense