Here is a suggestion that should appease both trader and pirate.
Vengeance of Witch Doctor Special Ability (Avenge and Pirate's Bonus)
Avenge = If player has cast voodoo on you during a 5 hour period, you may cast Vengeance on him and every cast highers his fleet danger by 2 (DOES NOT GO INTO EFFECT IF VOODOO IS STILL ON).
Pirate's Bonus = If a player has 0 fleets, every vengeance cast on another player will result in a +1 danger on target fleet.
^
Before someone points on a pirate can just remove ships from fleet, that is the PURPOSE of this idea! This gives the merchant enough time to commandeer the Pirate's ships if the merchant is on. This would be a fairly slow process alone and match a Pirate's lust for risk.
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