We were at a loss last night in our first game with the Swashbuckler. He got up to a strength of 12 or so.
He started in the Sentinel space and moved through the Sentinel, easily winning, then drawing a card in the middle region.
Then, because he won a "battle" (against the Sentinel), he took another turn, moving back to the outer region.
There, he drew two cards at a nearby field.
Now, during this second turn, one of these cards was a creature, which he defeated in battle.
So he took his third turn, going through the Sentinel and drawing a card.
During this third turn, he defeated the Sentinel yet again, so he gets a fourth turn.
And proceeds to land on a face-up enemy on the board.
So he is awarded with another... fifth turn, in which he defeats the Sentinel (easy, as he now has a 13+ strength)... giving him a sixth turn...
This was a five player game. During one of his many successive turns, the Swashbuckler drew and cast Temporal Warp. Had the player decided not to be merciful, we could have been sitting there for an hour or more as the Swashbuckler took turn after turn. Now, don't get me wrong, when a character has a 10+ strength, they should be close to winning the game anyway, but this isn't so much a balance issue as it is a fun-ness issue. Nobody else could play the game because of how the Swashbuckler was worded. He got several 2-3 turn in a row streaks earlier in the game, meaning that in total, nearly half of 5 player game's time was spent watching the Swasbuckler.
That's not to mention what happens if he has the Poltergeist and two weaker characters within one space of each other. He can theoretically hop back and forth until they're both stripped naked and dead.
In short, I think the "once per turn" restriction should be re-worded to "once per round," indicating that play must pass to all other players before the Swashbuckler can use his "take another turn" ability a second time. I'm curious to see what the community thinks on this.