I did this mission this morning, and it was easy to start - you just choose the South American location from the fast travel map. The mission reminds me of the Vlad mission in Brotherhood, and your prize is Captain Kidd's serrated sword; however, you need to visit a store to pick it up (doesn't cost you anything, it is just not automatically equipped).
Funny thing - I entered the code which allowed me to download the DLC. However it was only 100k in size so obviously the data is already on the disc, and this is simply just some sort of activation file.
These developers charge for just about everything.
Did that today! Nice change of scenario but the mission is incredibly easy... I was expecting a bit of a challenge!
I picked the sword but didn't bother equipping it since I only use axes in AC3! >:D
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