User blog comment:Obsidion Darkhart/Rank 4 hull upgrades... With fury broadsides!/@comment-4875046-20111016060620/@comment-4468389-20111016191817

you have to get ur upgrades and customization from sinking warships classes on the sea, like man o war pretty easy to sink behemoths war sloops and all that, any warship classes gives out stuff for upgrads and ship customization