These can be free (just like the ships) or upgrades that cost gold, up to rare's decision. The triangular sail is the exact opposite of the normal sail: it allows you to move faster against the wind, but it slows you down if you use it in favor of the wind. This could be super useful because the wind hates me. It could replace the normal sail (an option) or you can have both sails in your ship at the same time, up to rare's decision again.
PS: the "Lucky Rover" is always the unlucky ship in the arena
