Dynamic Campaign Generator (DCG) is a mod for the game "Men of War" and some of its successors that randomly generates skirmish missions and lets you keep your surviving forces from one battle to another. Some people find this mod tricky to install the first time - please read the readme.txt carefully and ask for help (if you need it) on our forums here on this site, or at the game developer's site.
How did u get a sea battle
You get these by transfering your unit from N.Afrika to fight on the main European continent, or vice versa (and you can only transfer your unit after a full campaign has been fought).
~Zeke.