I've enjoyed playing Camelot (the still-in-print French edition of Ivanhoe) as a two-player game with my daughter, but thought it would play better with three. Yet our first three-player game was bad -- the "stunned" card seems overpowering in a game with more than 2 players because it routinely excludes whomever it is played on from tournaments (they'd have to have a single card that overpowered the two (or more cards) played in the round prior to their turn). Limited participation in tournaments, in turn, drastically reduces the number of times the stunned player draws a new card, thereby making it pretty unlikely that s/he will draw the one card that can undo "stunned" after it has been played. So, basically, you have player elimination.
Is this how it usually works, or was our bad experience the result of inexperience? I ask because the player who played stunned ended up losing because he was left alone to battle the leader. His conclusion was "oops, played that too early -- I'll wait next time."
The Stunned card (just like the Shield) only remains until the person with that card in their display either wins or drops out of the tournament. In either case all displayed cards, including Stunned and Shield, are put in the discard pile.