Re: Assassins Creed 4 Black Flag
open the map, there is a legendary ship icon on each corner, go towards it and you will fight the legendary ship. i suggest starting with south-east.
they are: north east: 2 powerfull man of wars, 10000 reales each. when you sink one the other gets a powerup. i say its hardest. YOU CAN KILL ONE, LOOT IT, LEAVE, AND REDO THE FIGHT FROM THE START, FREE MONEY
north west:masiive ship with an insanely powerfull and almost unavoidable ram, if it hits you, you basicaly sink. 20000 reales
south west: hugely armoured ship, takes no/almost no damage from the sides. fires lots of mortars. 20000 reales
south east: some sort of ghost ship, you fight it in a foggy area with pointless flashes every 5 seconds. easy if you keep your eye on the ship.20000 reales
when you sink all 4 (or 5) you get an achievment, and the charge attack, which, not to put to fine a point on it, can cripple a frigate. in one hit.